As filed with the Securities and Exchange Commission on May 12,June 19, 2015

Registration No. 333-[            ]333-204088

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 2

to

Form S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

FIRST FINANCIAL BANKSHARES, INC.

(Exact name of registrant as specified in its charter)

400 Pine Street

Abilene, Texas 79601

(325) 627-7155

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

F. Scott Dueser

Chairman of the Board, President and Chief Executive Officer

First Financial Bankshares, Inc.

400 Pine Street

Abilene, Texas 79601

(325) 627-7155

(325) 627-7393 (Fax)

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after this registration statement becomes effective and all other conditions to the proposed merger described herein have been satisfied or waived.

If the securities being registered on this form are to be offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box:  ¨

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

CALCULATION OF REGISTRATION FEE

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this proxy statement/prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This proxy statement/prospectus is not an offer to sell these securities, and it is not soliciting to buy these securities, in any state where the offer or sale is not permitted.

PRELIMINARY—SUBJECT TO COMPLETION, DATED MAY 12,JUNE 19, 2015

FBC BANCSHARES, INC.

PROPOSED MERGER—YOUR VOTE IS VERY IMPORTANT

Dear Shareholder:

You are cordially invited to attend the special meeting of shareholders of FBC Bancshares, Inc., referred to as FBC, to be held on [                    ]July 23, 2015 at [        ]1:00 p.m. in the [            ].at FBC’s office located at 1800 West White Oak Terrace, Conroe, Texas 77304. At this important special meeting, you will be asked to approve the Agreement and Plan of Reorganization, dated April 1, 2015 (the “reorganization agreement”), by and between First Financial Bankshares, Inc., referred to as First Financial, and FBC, which provides for the acquisition of FBC by First Financial. The acquisition of FBC by First Financial will be completed by means of a merger of FBC Acquisition Corp., a wholly-owned subsidiary of First Financial, with and into FBC, on the terms and subject to the conditions contained in the reorganization agreement. You may also be asked to adjourn or postpone the meeting to a later date or dates, if the board of directors of FBC determines it is necessary.

If the merger is completed, all outstanding shares of FBC common stock will be converted, pursuant to the reorganization agreement, into the right to receive a total number of shares of First Financial common stock with an expected aggregate value of approximately $59 million, subject to certain adjustmentsadjustment between a range of $57 million to $61 million of aggregate consideration based on the average price per share of First Financial’s common stock during the measurement period set forth in accordancethe reorganization agreement. Additionally, the aggregate consideration will be reduced on a dollar-for-dollar basis in the event that FBC’s consolidated shareholders’ equity, as calculated under the reorganization agreement, is less than $14,705,000 at closing. At the time of the shareholders meeting, FBC shareholders will not know the exact number of shares or the value of the First Financial common stock that will be issued in connection with the terms of the reorganization agreement.merger. Based on the closing price of First Financial common stock on [                    ],June 17, 2015, shareholders of FBC would receive an aggregate number of shares of First Financial common stock equal to approximately [    ]%2.8% of the issued and outstanding shares of First Financial common stock after completion of the merger. First Financial’s common stock is listed on the NASDAQ Global Select Market under the symbol “FFIN.”

The board of directors of FBC has determined that the reorganization agreement and the transactions contemplated therein, including the merger, are fair to and in the best interests of FBC and its shareholders, and approved and declared advisable the reorganization agreement and the transactions contemplated therein, including the merger. The FBC board of directors recommends that you vote “FOR” the proposal to approve the reorganization agreement.

It is intended that the transactions contemplated by the reorganization agreement will be treated as reorganization for federal income tax purposes under Section 368(a) of the Internal Revenue Code of 1986, as amended.

We cannot complete the merger unless we obtain the necessary governmental approvals and the holders of at least two-thirds of the outstanding shares of FBC common stock approve the reorganization agreement.

Your vote is very important. Whether or not you plan to attend the special meeting, please take the time to vote by completing and mailing the enclosed proxy card to FBC. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting. If you sign, date and mail your proxy card without indicating your vote, your proxy will be counted as a vote “FOR” the proposal to adopt and approve the reorganization agreement and the transactions contemplated thereby. If you do not return your proxy card, abstain from voting or do not instruct your brokerage firm, bank, trust or other nominee how to vote any shares held for you in “street name,” the effect will be a vote “AGAINST” such proposal.

This document contains a more complete description of the special meeting, the reorganization agreement and the transactions contemplated therein, including the merger. We urge you to review this entire document carefully. You may also obtain information about First Financial from documents that First Financial has filed with the Securities and Exchange Commission, referred to as the “SEC.”

H.J. Shands, III

Chairman of the Board

FBC Bancshares, Inc.

An investment in First Financial common stock in connection with the merger involves risks. See“Risk Factors” beginning on page 16.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED THE MERGER OR OTHER TRANSACTIONS DESCRIBED IN THE ATTACHED PROXY STATEMENT/PROSPECTUS OR THE SECURITIES TO BE ISSUED PURSUANT TO THE MERGER UNDER THE ATTACHED PROXY STATEMENT/ PROSPECTUS NOR HAVE THEY DETERMINED IF THE ATTACHED PROXY STATEMENT/ PROSPECTUS IS ACCURATE OR ADEQUATE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The securities that First Financial is offering through this document are not savings or deposit accounts or other obligations of any bank or non-bank subsidiary of either of First Financial or FBC, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

Proxy statement/prospectus dated [                    ],June 19, 2015 and first mailed to shareholders of FBC on or about [                    ], 2015June 24, 2015.

HOW TO OBTAIN ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates important business and financial information about First Financial from documents filed with the SEC that have not been included in or delivered with this document. This information is described on page 68 under “Where You Can Find More Information.” You can obtain free copies of this information by writing or calling:

First Financial Bankshares, Inc.

400 Pine Street

Abilene, Texas 79601

Attention: J. Bruce Hildebrand, Executive Vice President and Chief Financial Officer

Telephone (325) 627-7155

To obtain timely delivery of the documents before the special meeting of FBC, you must request the information by [                    ],July 16, 2015.

PLEASE NOTE

We have not authorized anyone to provide you with any information other than the information included in this document and the documents to which we refer you. If someone provides you with other information, please do not rely on it as being authorized by us.

This proxy statement/prospectus has been prepared as of [                    ],June 19, 2015. There may be changes in the affairs of FBC or First Financial since that date, which are not reflected in this document.

FBC BANCSHARES, INC.

1800 West White Oak Terrace

Conroe, Texas 77304

(936) 760-1888

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

NOTICE IS HEREBY GIVEN that a special meeting of the shareholders of FBC Bancshares, Inc., or FBC, will be held on [                    ],July 23, 2015, at [                    ]1:00 p.m., local time, at [                    ],FBC’s office located at 1800 West White Oak Terrace, Conroe, Texas 77304, for the following purposes:

Only shareholders of record at the close of business on [                    ],June 19, 2015 will be entitled to notice of and to vote at the special meeting and any adjournments or postponements thereof. The special meeting may be adjourned or postponed from time to time upon approval of FBC’s shareholders without any notice other than by announcement at the meeting of the adjournment or postponement thereof, and any and all business for which notice is hereby given may be transacted at such adjourned or postponed meeting.

Shareholders of FBC have the right to dissent from the merger and obtain payment in cash of the appraised fair value of their shares of FBC common stock under applicable provisions of the Texas Business Organizations Code. In order for a shareholder of FBC to perfect its right to dissent, such shareholder must file a written objection to the merger prior to the special meeting, must vote against the reorganization agreement and must file a written demand with First Financial within 20 days after the consummation of the merger for payment of the fair value of the shareholder’s shares of FBC common stock. A copy of the applicable statutory provisions of the Texas Business Organizations Code is included asAppendix Cto the accompanying proxy statement/prospectus and a summary of these provisions can be found under the caption “Proposal 1: Approval of the Reorganization Agreement—Dissenters’ Rights of FBC Shareholders.”

The board of directors of FBC unanimously recommends that you vote (i) FOR the approval of the reorganization agreement and (ii) FOR the proposal to adjourn the special meeting, if necessary or advisable, to permit further solicitation of proxies.

By Order of the Board of Directors,

H. J. Shands, III

Chairman of the Board

FBC Bancshares, Inc.

Conroe, Texas

[                    ],June 19, 2015

Your Vote is Very Important

A proxy card is enclosed. Whether or not you plan to attend the special meeting, please complete, sign and date the proxy card and promptly mail it in the enclosed envelope. You may revoke your proxy card in the manner described in the proxy statement/prospectus at any time before the special meeting is called to order. If you attend the special meeting, you may vote in person if you wish, even if you have previously returned your proxy card.

TABLE OF CONTENTS

i

ii

QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

As of the date of this proxy statement/prospectus, FBC’s board of directors is not aware of any matters, other than those stated above, that may be brought before the special meeting.

The merger cannot be completed unless FBC common shareholders approve the reorganization agreement. FBC is holding a special meeting of its shareholders to vote on the proposal to approve the reorganization agreement as well as other related matters. Information about this special meeting, the merger and the other business to be considered by shareholders at the special meeting is contained in this document.

This document constitutes both a proxy statement of FBC and a prospectus of First Financial. It is a proxy statement because the FBC board of directors is soliciting proxies from FBC common shareholders using this document with respect to the matters to be considered at the special meeting. It is a prospectus because First Financial, in connection with the merger, is offering shares of its common stock in exchange for outstanding shares of FBC common stock in the merger.

The number of shares to be issued by First Financial will fluctuate based on the average price per share of First Financial’s common stock. The aggregate merger consideration will also range from $57.0 million to $61.0 million based on the average price per share of First Financial’s common stock. For illustration purposes only and disregarding certain adjustments described in the reorganization agreement, based on First Financial’s closing stock price of $[        ]$32.62 on [                    ],June 17, 2015 and assuming that 884,600 shares of FBC common stock are outstanding at the effective time of the merger, FBC stockholders would have received [            ]2.1 shares of First Financial common stock for each share of FBC common stock, which would have provided FBC stockholders with aggregate ownership, on a pro forma basis, of approximately [    ]%2.8% of the common stock of First Financial following the merger.

In addition, the merger consideration will be reduced on a dollar-for-dollar basis in the event that FBC’s consolidated shareholders’ equity as of the close of business on the business day immediately preceding the closing date of the merger, after certain adjustments prescribed by the reorganization agreement have been made, is less than $14,705,000. To the extent that FBC’s consolidated shareholders’ equity exceeds $14,705,000, FBC may dividend the excess amount to its shareholders prior to closing.

The actual merger consideration is subject to adjustment and may be higher or lower than the consideration described in the examples above. Because the per share merger consideration will be determined based upon the twenty-day average price of First Financial’s common stock and the adjusted consolidated shareholders’ equity of FBC, the amount of consideration you will receive will not be known at the time you vote on the reorganization agreement. Accordingly, you should read this proxy statement/prospectus carefully to understand the value of the consideration you will receive in the merger. For an explanation of how the merger consideration will be calculated, please see “Proposal 1: Approval of the Reorganization Agreement—Terms of Merger,” beginning on page 23.

For further information, please see to “Proposal 1: Approval of the Reorganization Agreement—Material U.S. Federal Income Tax Consequences of the Merger.” The U.S. federal income tax consequences described above may not apply to all holders of FBC common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your tax advisor for a full understanding of the particular tax consequences of the merger to you.

Q:	When and where will the FBC shareholders’ meeting be held?

Proposal 1—FOR the proposal to approve the reorganization agreement; and

Proposal 2—FOR any proposal to adjourn the special meeting to a later date or dates, if the board of directors of FBC determines such an adjournment is necessary to permit further solicitation of additional proxies.

Q:	May I change my vote after I have submitted my proxy card?

RISK FACTORS

In addition to general investment risks and the other information contained in or incorporated by reference into this proxy statement/prospectus, including the matters addressed under the section “Cautionary Statement Regarding“A Warning About Forward-Looking Statements” beginning on page 19 and the matters discussed under the caption “Risk Factors” in Annual Report on Forms 10-K filed with the SEC by First Financial, for the year ended December 31, 2014, as updated by other reports filed with the SEC, you should carefully consider the following risk factors in deciding how to vote on the proposals presented in this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 68.

The merger may not be completed.

Completion of the merger is subject to regulatory approval. First Financial cannot assure you that it will be successful in obtaining required regulatory approvals. If First Financial is not successful in obtaining required regulatory approvals, the merger will not be completed. If such regulatory approvals are received, there can be no assurance to the timing of those approvals or whether any conditions will be imposed that would result in certain closing conditions of the merger not being satisfied.

The consummation of the merger is also subject to other conditions precedent described in the reorganization agreement. If a condition of either party is not satisfied, the other party may be able to terminate the reorganization agreement and, in such case, the transaction would not be consummated. The parties cannot assure you that all of the conditions precedent in the reorganization agreement will be satisfied or that the merger will be completed.

The number of shares of First Financial common stock received as merger consideration will fluctuate, and shareholders of FBC may receive more or less value, depending upon increases and decreases in market price of First Financial’s common stock and the consolidated shareholders’ equity of FBC prior to closing.

The aggregate number of shares of First Financial stock issued to FBC shareholders in exchange for each share of FBC will fluctuate based upon changes in the market price of First Financial’s common stock and the consolidated shareholders’ equity of FBC prior to the closing of the merger. The consolidated shareholders’ equity of FBC at the time the merger is completed may vary from the consolidated shareholders’ equity at the date the reorganization agreement was executed, the date of this document and at the date of the shareholders’ meeting of FBC.

Changes in the value of the merger consideration may be the result of various factors, many of which are beyond the control of First Financial and FBC, including:

The merger may not be completed until a significant period of time has passed after the FBC’s shareholders’ meeting. At the time of the shareholder meeting, FBC shareholders will not know the exact number of shares or the value of the First Financial common stock that will be issued in connection with the merger.

The market price of First Financial common stock after the merger may be affected by factors different from those affecting FBC common stock or First Financial common stock currently.

The businesses of First Financial and FBC differ in some respects and, accordingly, the results of operations of the combined company and the market price of First Financial’s shares of common stock after the merger may

be affected by factors different from those currently affecting the independent results of operations of each of First Financial and FBC. For a discussion of the business of First Financial and of certain factors to consider in connection with that business, see the documents incorporated by reference into this proxy statement/prospectus and referred to under “Where You Can Find More Information.”

Regulatory approvals may not be received, may take longer than expected or impose conditions that are not presently anticipated.

The Federal Reserve must approve First Financial’s acquisition of FBC and the OCC must approve the merger of First Bank with and into First Financial Bank. On April 10, 2015, First Financial filed an application with the Federal Reserve to obtain approval of the merger under the BHC Act and First Financial Bank and First Bank filed an application with the OCC to obtain approval of bank merger. First Financial received such approvals from the Federal Reserve and the OCC on May 20, 2015 and May 22, 2015, respectively. The Federal Reserve and the OCC will consider,considers, among other factors, the competitive impact of the merger, the financial and managerial resources of our companies and our subsidiary banks and the convenience and needs of the communities to be served. As part of that consideration, we expect that the Federal Reserve and OCC will reviewreviewed issues related to capital position, safety and soundness, and legal and regulatory compliance, including compliance with anti-money laundering laws. There can be no assurance as to whether this and other regulatory approvals will be received, the timing of those approvals or whether any conditions will be imposed.

Shareholders should bear in mind that regulatory approval reflects only the view that the merger does not contravene applicable competitive standards imposed by law, and that the merger is consistent with regulatory policies relating to safety and soundness. Further, regulatory approval is not an opinion that the proposed merger is favorable to the shareholders of either party to the merger from a financial point of view or that the regulatory authority has considered the adequacy of the terms of the merger. Regulatory approval is not an endorsement or recommendation of the merger.

FBC will be subject to business uncertainties while the merger is pending.

Uncertainty about the effect of the merger on employees and customers of FBC may have an adverse effect on FBC and its wholly-owned subsidiary, First Bank, and consequently on First Financial following completion of the merger. These uncertainties may impair FBC’s ability to attract, retain and motivate key personnel until the merger is completed, and could cause customers and others that deal with FBC to seek to change existing business relationships with FBC. Retention of certain employees of FBC and First Bank may be challenging while the merger is pending, as certain employees may experience uncertainty about their future roles with First Financial. If key employees depart, First Financial’s business following the merger could be harmed. See the section entitled “Proposal 1: Approval of the Reorganization Agreement—Conduct of Business Pending Effective Time” beginning on page 35 of this proxy statement/prospectus for a description of the restrictive covenants to which FBC is subject.

Combining our two banks may be more difficult, costly or time-consuming than we expect.

First Financial Bank and First Bank have historically operated and, until the bank merger is completed, will continue to operate, independently. It is possible that the integration process could result in the loss of key employees or disruption of each bank’s ongoing business or inconsistencies in standards, controls, procedures and policies that adversely affect our ability to maintain relationships with customers and employees or to achieve the anticipated benefits of the merger. As with any combination of banking institutions, there also may be business disruptions that cause us to lose customers or cause customers to take their deposits out of our banks. The success of the combined bank following the merger may depend in large part on the ability to integrate the two businesses, business models and cultures. If we are not able to integrate our operations successfully and timely, the expected benefits of the merger may not be realized.

Some of the directors and officers of FBC may have interests and arrangements that may have influenced their decisions to support or recommend that you approve the reorganization agreement and the transactions contemplated therein.

The interests of some of the directors and officers of FBC may be different from those of FBC shareholders, and such directors and officers may be participants in arrangements that are different from, or in addition to, those of FBC shareholders. These interests are described in more detail in the section of this proxy statement/prospectus entitled “Proposal 1: Approval of the Reorganization Agreement—Financial Interests of Directors and Officers of FBC in the Merger”beginning on page 43.

First Financial may fail to realize the cost savings estimated for the merger.

Although First Financial estimates that it will realize cost savings from the merger when integrated, it is possible that the estimates of the potential cost savings could turn out to be incorrect. For example, the combined purchasing power may not be as strong as expected, and therefore the cost savings could be reduced. In addition, unanticipated growth in First Financial’s business may require First Financial to continue to operate or maintain some facilities or support functions that are currently expected to be combined or reduced. The cost savings estimates also depend on our ability to combine the businesses of First Financial Bank and First Bank in a manner that permits those costs savings to be realized. If the estimates turn out to be incorrect or First Financial is not able to combine successfully the two banks, the anticipated cost savings may not be fully realized or realized at all, or may take longer to realize than expected.

FBC shareholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management.

The merger will transfer control of FBC to First Financial and to the shareholders of First Financial. When the merger is completed, each FBC shareholder (other than dissenting shareholders) will become a shareholder of First Financial with a percentage ownership of First Financial much smaller than such shareholder’s percentage ownership of FBC. Because of this, FBC shareholders will have less influence on the management and policies of First Financial, and thus First Financial Bank, than they now have on the management and policies of FBC.

A WARNING ABOUT FORWARD-LOOKING STATEMENTS

Certain statements contained in this proxy statement/prospectus, including statements included or incorporated by reference in this proxy statement/prospectus, that are not statements of historical fact constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties. These forward-looking statements include information about possible or assumed future results of operations of First Financial after the merger is completed as well as information about the merger. Words such as “believes,” “expects,” “anticipates,” “estimates,” “intends,” “continue,” “should,” “may,” or similar expressions, or the negatives thereof, are intended to identify forward-looking statements, but are not the exclusive means of identifying such statements. Many possible events or factors could affect the future financial results and performance of each of our companies before the merger or First Financial after the merger, and could cause those results or performance to differ materially from those expressed in the forward-looking statements. These possible events or factors include, but are not limited to:

For other factors, risks and uncertainties that could cause actual results to differ materially from estimates and projections contained in forward-looking statements, please read the “Risk Factors” section of this proxy statement/prospectus.

A forward-looking statement may include a statement of the assumptions or bases underlying the forward-looking statement. We believe we have chosen these assumptions or bases in good faith and that they are reasonable. However, we caution you that assumptions or bases almost always vary from actual results, and the differences between assumptions or bases and actual results can be material. Therefore, we caution you not to place undue reliance on our forward-looking statements. The forward-looking statements are made as of the date of this proxy statement/prospectus or the date of the applicable document incorporated by reference into this proxy statement/prospectus. We undertake no obligation to publicly update or otherwise revise any forward-looking statements, whether as a result of new information, future events or otherwise.

GENERAL INFORMATION

This document constitutes a proxy statement of FBC and is being furnished to all record holders of FBC common stock in connection with the solicitation of proxies by the board of directors of FBC to be used at the special meeting of shareholders of FBC to be held on [                    ],July 23, 2015. The purpose of the FBC special meeting is to consider and vote to approve the reorganization agreement, dated April 1, 2015, by and between First Financial and FBC, and the transactions contemplated by the reorganization agreement including, among other things, the merger of FBC Acquisition Corp.,a wholly-owned subsidiary of First Financial, with and into FBC, with FBC surviving the merger as a wholly-owned subsidiary of First Financial.

This document also constitutes a prospectus relating to the First Financial common stock to be issued to shareholders of FBC common stock upon completion of the merger.

FBC SPECIAL SHAREHOLDERS’ MEETING

Date, Place and Time of the Special Meeting

The special meeting of shareholders of FBC will be held on [                    ],July 23, 2015 at [            ],1:00 p.m., local time, at [            ].FBC’s office located at 1800 West White Oak Terrace, Conroe, Texas 77304. The special meeting may be postponed to another date or place for proper purposes, including for the purpose of soliciting additional proxies.

Purpose

The purpose of the special meeting are to consider and vote on the following:

At this time, the board of directors of FBC and the voting representatives are unaware of any matter, other than the matter set forth above, that may be presented for action at the special meeting.

Record Date; Shares Entitled to Vote

The close of business on [                    ]June 19, 2015 is the record date. The holders of record of the outstanding shares of FBC common stock as of the close of business on the record date are entitled to notice of, and to vote at, the special meeting, or any postponement thereof. At the close of business on the record date, there were 884,600 shares of FBC common stock outstanding and entitled to vote at the special meeting. At the special meeting, the shareholders of FBC will be entitled to one vote for each share of common stock owned as of the close of business on the record date.

Quorum; Vote Required

The holders of a majority of the shares of FBC common stock entitled to vote at the special meeting must be present, either in person or by proxy, to constitute a quorum at the special meeting. Approval of the reorganization agreement requires the affirmative vote of the holders of at least two-thirds of the outstanding shares of FBC common stock entitled to vote. If you fail to vote, it will have the effect of a vote against the reorganization agreement.

Shares Held by Directors and Executive Officers

As of the record date, all of the directors of FBC (5 persons) and executive officers of FBC were entitled to vote 232,051 shares of FBC common stock, or approximately 26.2% of the outstanding shares of the common stock entitled to vote at the special meeting. Each of the directors has executed a Voting Agreement and Irrevocable Proxy, dated as of April 1, 2015, referred to as the “voting agreement” in this proxy statement/prospectus, pursuant to which each director agreed to vote his shares of FBC common stock in favor of approval of the merger pursuant to the reorganization agreement. In addition to the directors, certain shareholders of FBC have entered into the voting agreement. As of the record date, 714,098 shares of FBC common stock, or approximately 80.7% of the outstanding shares of FBC common stock entitled to vote at the FBC special meeting, are bound by the voting agreement. Accordingly, approval of the merger pursuant to the reorganization agreement by the FBC shareholders is assumed.

Voting and Revocation of Proxies

Any holder of record of shares of FBC common stock entitled to vote may submit a proxy by returning a signed proxy card by mail, or may vote in person by appearing at the special meeting. Proxies, in the form enclosed, which are properly executed and returned to FBC and not subsequently revoked, will be voted in accordance with the instructions indicated on the proxies. Any properly executed proxy on which voting instructions are not specified will be voted FOR the proposal to approve the merger pursuant to the reorganization agreement. The proxy also grants authority to the persons designated in such proxy to vote in accordance with their own judgment if an unscheduled matter is properly brought before the special meeting.

If you are a beneficial owner and hold your shares of FBC common stock in “street name” through a brokerage firm, bank, trust or other nominee, you should instruct your nominee on how you wish to vote your shares of FBC common stock using the instructions provided by your nominee. Under applicable rules, brokerage firms, banks, trusts and other nominees have the discretion to vote on routine matters. The merger proposal is a non-routine matter, and brokerage firms, banks, trusts and other nominees cannot vote on these proposals without your instructions. Therefore, it is important that you cast your vote or instruct your brokerage firm, bank, trust or other nominee on how you wish to vote your shares of FBC common stock.

If you do not return your proxy card or attend the special meeting, your shares of FBC common stock will not be voted, which will have the same effect as a vote against the merger. Even if you plan to attend the special meeting, if you hold your shares of FBC common stock in your own name as the shareholder of record, please vote your shares of FBC common stock by completing, signing, dating and returning the enclosed proxy card.

If you are the record holder of your shares, you may revoke any proxy given pursuant to this solicitation by the board of directors of FBC at any time before it is voted at the special meeting by:

All written notices of revocation and other communications with respect to revocation or proxies must be received by FBC no later than [                    ],July 22, 2015, at 5:00 p.m. local time, which is the business day immediately prior to the special meeting and should be sent to: FBC Bancshares, Inc., 1800 West White Oak Terrace, Conroe, Texas 77304, Attention: Secretary. If you hold your shares in street name with a brokerage firm, bank, trust or other nominee, you must contact such brokerage firm, bank, trust or other nominee if you wish to revoke your proxy.

Your presence without voting at the special meeting will not automatically revoke your proxy, and any revocation during the special meeting will not affect votes previously taken.

The secretary of FBC will determine all questions as to validity, form, eligibility (including time of receipt) and acceptance of proxies. Its determination will be final and binding. The board of directors has the right to waive any irregularities or conditions as to the manner of voting. FBC may accept your proxy by any form of communication permitted by the TBOC so long as FBC is reasonably assured that the communication is authorized by you.

Shares Held in Street Name

Your brokerage firm, bank, trust or other nominee cannot vote your shares of FBC common stock for or against approval and adoption of the merger proposal unless you tell the brokerage firm, bank, trust or other nominee how you wish to vote. To tell your nominee how to vote, you should follow the directions that your nominee provides to you. Please note that you may not vote your shares of FBC common stock held in “street name” by returning a proxy card directly to FBC or by voting in person at the special meeting unless you provide a “legal proxy,” which you must obtain from your nominee. If you do not instruct your broker or other nominee on how to vote your shares of FBC common stock, your broker or other nominee may not vote your FBC common shares, which will have the same effect as a vote against the merger proposal for purposes of the required vote. You should therefore provide your brokerage firm, bank, trust or other nominee with instructions as to how to vote your shares of FBC common stock.

Solicitation of Proxies; Expenses

This proxy solicitation is made by the board of directors of FBC. FBC is responsible for its expenses incurred in preparing, assembling, printing and mailing this proxy statement/prospectus. Proxies will be solicited through the mail. Additionally, directors of FBC intend to solicit proxies personally or by telephone or other means of communication. The directors will not be additionally compensated. FBC will reimburse banks, brokers and other custodians, nominees and fiduciaries for their reasonable expenses in forwarding the proxy materials to beneficial owners.

Recommendation of FBC’s Board of Directors

After considering various factors described in the section entitled “Proposal 1: Approval of the Reorganization Agreement—Recommendation of FBC’s Board of Directors and its Reasons for the Merger,” the board of directors of FBC has unanimously determined that the reorganization agreement and the transactions contemplated by the reorganization agreement, including the merger, are advisable and in the best interests of FBC’s shareholders and has adopted and approved the reorganization agreement and the transactions contemplated by the reorganization agreement, including the merger. The board of directors recommends that you vote “FOR” the proposal to adopt and approve the reorganization agreement.

Dissenters’ Rights

Holders of shares of FBC common stock are entitled to dissenters’ rights under Subchapter H of Chapter 10 of the TBOC, provided they satisfy the conditions set forth therein. For a more detailed discussion of your dissenters’ rights and the requirements for perfecting your dissenters’ rights, see “Proposal 1: Approval of the Reorganization Agreement—Dissenters’ Rights of FBC Shareholders” on page 50. In addition, a copy of Subchapter H of Chapter 10 of the TBOC is attached as Annex C to this proxy statement/prospectus.

PROPOSAL 1: APPROVAL OF THE REORGANIZATION AGREEMENT

The following information describes material aspects of the merger pursuant to the reorganization agreement. It is not intended to be a complete description of all information relating to the merger pursuant to the reorganization agreement and is qualified in its entirety by reference to more detailed information contained in the appendices to this document, including the reorganization agreement. A copy of the reorganization agreement is included asAppendix A and is incorporated herein by reference. You are urged to read the appendices in their entirety.

Terms of the Merger

Structure of Merger. The reorganization agreement provides for the acquisition of FBC and its wholly-owned subsidiary, First Bank, by First Financial. If (i) the shareholders of FBC approve the merger pursuant to the reorganization agreement at the special meeting, (ii) the required regulatory approvals are obtained and (iii) the other conditions to the parties’ obligations to effect the transactions contemplated by the reorganization agreement are met or waived by the party entitled to do so, we anticipate that the transactions contemplated by the reorganization agreement will be completed in July 2015, although delays could occur.

The first transaction contemplated by the reorganization agreements is the merger of FBC Acquisition Corp., a wholly-owned, transitory subsidiary of First Financial, with and into FBC, with FBC surviving the merger as a wholly-owned subsidiary of First Financial. As a result of the merger, holders of FBC common stock as of the effective time of the merger will be entitled to receive whole shares of First Financial common stock and, in some instances, cash, with additional cash payable in lieu of any fractional share. Following the merger, certificates for FBC common stock will only represent the right to receive the merger consideration pursuant to the reorganization agreement, and otherwise will be null and void.

Following immediately after the merger, First Financial will cause (i) FBC to merge with and into First Financial, with First Financial as the surviving entity and FBC ceasing its separate corporate existence and (ii) First Bank to merge with and into First Financial Bank, with First Financial Bank as the surviving bank and First Bank ceasing its separate corporate existence. As a result of the bank merger, the existing branches and main office of First Bank will become branches of First Financial Bank.

Consideration. The number of shares of First Financial common stock deliverable for each share of FBC common stock will be determined based on the average daily closing price of First Financial’s common stock on the NASDAQ Global Select Market for each of the twenty consecutive trading days ending on the fifth business day immediately preceding the closing date of the merger, referred to as the “FFIN Market Price” in this proxy statement/prospectus. Subject to the terms of the reorganization agreement, the general method for calculating the number of shares to be issued for each share of FBC common stock is to divide the aggregate merger consideration by (i) the number of shares of FBC common stock outstanding, less certain adjustments and (ii) the FFIN Market Price. Subject to the adjustments set forth in the reorganization agreement, the aggregate merger consideration will be determined as follows:

for each share of FBC common stock, which would have provided FBC stockholders with aggregate ownership, on a pro forma basis, of approximately [    ]%2.8% of the common stock of First Financial following the merger.;

Regardless of the FFIN Market Price, the maximum number of shares of First Financial common stock that First Financial is required to issue under the reorganization agreement is 2,231,941 shares of First Financial common stock (the “FFIN Share Cap”). To the extent that the aggregate merger consideration due to the holders of FBC common stock pursuant to the reorganization agreement exceeds the value of shares of First Financial common stock equal to the FFIN Share Cap, First Financial may, in its sole discretion, (i) increase the number of shares of First Financial common stock issued in excess of the FFIN Share Cap, (ii) increase the number of shares of First Financial common stock issued in excess of the FFIN Share Cap and pay an additional cash amount, or (iii) pay an additional cash amount.

Consideration Examples. The following table, which is for illustration purposes only, provides examples of the consideration that would be payable to holders of FBC common stock based upon the FFIN Market Prices listed in the table. The table does not reflect all possible adjustments that may be made to the merger consideration that are set forth in the reorganization agreement including, without limitation, possible adjustments for the consolidated shareholders’ equity or that cash will be paid instead of fractional shares. The following table assumes that 884,600 shares of FBC common stock will be outstanding as of the effective time of the merger. The actual prices at which First Financial common stock trades will establish the actual FFIN Market Price. The actual trading price of First Financial common stock is subject to market fluctuations.

Downward Adjustment of Consideration. The aggregate merger consideration to be paid pursuant to the reorganization agreement will be reduced on a dollar-for-dollar basis in the event that FBC’s consolidated shareholders’ equity as of the close of business on the business day immediately preceding the closing date of the merger, after certain adjustments prescribed by the reorganization agreement have been made, is less than $14,705,000.

Dividend of Excess Shareholders’ Equity. To the extent that FBC’s consolidated shareholders’ equity as of the close of business on the business day immediately preceding the closing date of the merger, after certain adjustments prescribed by the reorganization agreement have been made, exceeds $14,705,000, FBC may dividend the excess amount to its shareholders prior to closing.

Debt Repayment. First Financial has also agreed to redeem all of FBC’s Subordinated Promissory Notes due June 30, 2028 within three business days of the closing date of the merger. The Subordinated Promissory Notes due June 30, 2028 had an aggregate outstanding principal balance of $13,125,000 as of April 1, 2015.

The actual merger consideration is subject to adjustment and may be higher or lower than the consideration described in the examples above. Because the per share merger consideration will be determined based upon the price of First Financial’s common stock and the adjusted consolidated shareholders’ equity of FBC, the amount of consideration you will receive will not be known at the time you vote on the reorganization agreement. Accordingly, you should read this proxy statement/prospectus carefully to understand the value of the consideration you will receive in the merger.

Background of the Merger

The FBC board of directors periodically has reviewed FBC’s performance, compared its performance with that of certain comparable institutions, reviewed the limited market activity in FBC’s common stock, considered various business opportunities and strategies available to FBC and discussed the general economic, regulatory, competitive and business pressures affecting FBC and First Bank. In addition, the FBC board of directors, on an informal basis and during strategic planning sessions, would periodically review merger and acquisition activity in the banking industry.

In November 2012, F. Scott Dueser, Chairman of the Board, President and Chief Executive Officer of First Financial, contacted Sam W. Baker, President of FBC and President and Chief Executive Officer of the First Bank, by telephone to preliminarily discuss a possible business combination between First Financial and First Bank (FBC had not been formed at that time). Messrs. Dueser and Baker spoke again by telephone in June 2013 for further discussions regarding a possible business combination. At each of these meetings, Mr. Baker, indicated that FBC was not ready to sell, but that FBC may be interested in a transaction in the future. Mr. Baker reported each of those conversations to H. J. Shands, III, Chairman of the Board of FBC and First Bank, who in turn disclosed them to FBC’s board of directors.

In September 2013, Mr. Baker introduced Mr. Dueser to Mr. Shands by telephone and the parties briefly discussed a proposed business combination and the possibility of FBC and First Bank moving forward with a transaction. In March 2014, Messrs. Shands and Baker visited Mr. Dueser in Abilene, Texas. At this initial visit, the parties discussed the opportunities presented by a business combination between their institutions, the overall banking marketplace in southeast Texas and contiguous markets, the communities in which FBC and First Bank does business, the structure and nature of First Bank, and various potential transaction structures. Messrs. Dueser and Shands met in person again on May 9, 2014 in Colorado Springs, Colorado in furtherance of discussions regarding a proposed transaction.

Following the March and May 2014 meetings, the parties continued discussions regarding the terms and structure of a proposed transaction. As these discussions progressed, on September 24, 2014, First Financial and FBC entered into a confidentiality agreement to facilitate the exchange of information. In October 2014, Mr. Shands along with Messrs. Joe C. Denman, III and M. Richard Warner, each a director of FBC and First Bank, approached Vining Sparks regarding providing financial advice to FBC in connection with a potential corporate transaction involving FBC.

The discussions between the parties and Vining Sparks then turned toward structuring a formal offer from First Financial to FBC regarding a proposed merger transaction, including a preliminary price range. On October 15, 2015, representatives of Vining Sparks provided FBC with its initial analysis regarding the

preliminary pricing range and structure offered by First Financial, which analysis discussed the attractiveness of the proposal from a financial point of view. On October 22, 2014, First Financial submitted a formal offer to FBC in the form of a Letter of Intent. In the Letter of Intent, First Financial offered to purchase FBC for an aggregate purchase price of $59.0 million in the form of First Financial common stock, based on the market value of First Financial’s common stock at that time, and to pay FBC an additional $13.1 million to pay off its outstanding Subordinated Promissory Notes due June 30, 2028.

After input and recommendations of revisions to the Letter of Intent from the parties’ legal and financial advisors, FBC signed the revised Letter of Intent on October 22, 2014 and thereafter engaged Vining Sparks as its exclusive financial adviser in connection with the proposed transaction. This Letter of Intent had an expiration date of January 31, 2015 and a no-shop provision that prohibited FBC from pursuing and negotiating a transaction with another party during the term of the Letter of Intent.

Following the signing of the Letter of Intent, the executive management teams of First Financial and FBC met for dinner in The Woodlands, Texas on November 17, 2014 and discussed the proposed transaction.

During November and December 2014, the parties proceeded on an exclusive basis to perform regular and reverse due diligence investigations of each company and their respective subsidiaries. The two companies’ legal teams also began preparing and negotiating the terms of the reorganization agreement. During the due diligence period, First Financial conducted a thorough due diligence investigation of FBC. This due diligence investigation included on-site review of documents, files and other pertinent materials, including in-person meetings and discussions with key FBC personnel. FBC, together with its financial advisor, Vining Sparks and legal counsel, conducted a thorough reverse due diligence investigation of First Financial. This due diligence investigation included a review of current and historical public filings of First Financial and on-site review of material information and records of First Financial, as well as interviews with senior management.

In November 2014, the parties agreed that First Financial would directly repay FBC’s Subordinated Promissory Notes due June 30, 2028 rather than pay FBC cash for satisfying such debt obligations, as originally agreed.

From December 2014 through March 2015, management of First Financial and FBC negotiated the terms and conditions of the reorganization agreement, including, among other terms, the mix of consideration between stock and cash and price protection measures in the form of caps and collars applicable to the merger consideration. During this period, the term of the Letter of Intent was set to expire and First Financial and FBC agreed on January 14, 2015 to extend the deadline under the Letter of Intent until March 31, 2015 to allow the parties additional time to perform due diligence and negotiate the terms of the reorganization agreement.

The parties prepared several memoranda providing specific proposals of methodology for calculating the aggregate merger consideration and allocating risk related to any potential changes in First Financial’s market price, specifically in light of the recent volatility with the oil and gas industry and significant decreases in energy prices. After further negotiation, the parties agreed on a merger consideration calculation methodology based on a variable aggregate merger consideration with high and low collars of $61.0 million and $57.0 million, respectively, and a stock and cash mix based on any changes in First Financial’s average market value for a specified period prior to the closing date of the merger.

On March 16, 2015, FBC’s board of directors held a meeting to discuss the proposed transaction and the then current draft of the reorganization agreement. At that meeting, the FBC board of directors was briefed on the terms of reorganization agreement and the related agreements and had the opportunity to ask questions to FBC’s legal and financial advisors regarding terms and conditions of the transaction as set forth in the reorganization agreement. Vining Sparks also presented an analysis of the financial terms set forth in the reorganization agreement. Vining Sparks provided FBC’s board of directors with its opinion that consummation of the proposed transaction on those terms was fair to the shareholders of FBC from a financial point of view.

Following this discussion, and after due consideration and deliberation, the board of directors of FBC unanimously approved the transactions contemplated by the reorganization agreement, authorized the execution of the reorganization agreement and recommended the approval of the reorganization agreement and the transactions contemplated therein to the shareholders of FBC.

On April 1, 2015, First Financial and FBC entered into the definitive version of the reorganization agreement, the voting agreements and the director support agreements. FBC and First Financial also issued a press release announcing the transaction.

Recommendation of FBC’s Board and its Reasons for the Merger

FBC’s board of directors believes that the merger is in the best interest of FBC and its shareholders. Accordingly, FBC’s board of directors has unanimously approved the merger and the reorganization agreement and unanimously recommends that FBC’s shareholders vote FOR approval of the reorganization agreement.

In approving the reorganization agreement, FBC’s board of directors consulted with Vining Sparks with respect to the financial aspects and fairness of the merger consideration, from a financial point of view, to the holders of shares of FBC common stock and with its outside legal counsel as to its legal duties and the terms of the reorganization agreement. The board believes that combining with First Financial will create a stronger and more diversified organization that will provide significant benefits to FBC’s shareholders and customers alike.

The terms of the reorganization agreement, including the consideration to be paid to FBC’s shareholders, were the result of arm’s length negotiations between representatives of FBC and representatives of First Financial. In arriving at its determination to approve the reorganization agreement, FBC’s board of directors considered a number of factors, including the following:

The reasons set out above for the merger are not intended to be exhaustive but include the material factors considered by the board of directors of FBC in approving the merger and the reorganization agreement. In reaching its determination, the board of directors of FBC did not assign any relative or specific weight to different factors and individual directors may have given weight to different factors. Based on the reasons stated above, the board of directors of FBC believes that the merger is in the best interest of FBC and its shareholders and therefore the board of directors of FBC unanimously approved the reorganization agreement and the merger. Each member of FBC’s board of directors has agreed to vote the stock of FBC which he or she has voting authority in favor of the reorganization agreement and the merger.

THE BOARD OF DIRECTORS OF FBC UNANIMOUSLY RECOMMENDS THAT YOU VOTE (I) FOR THE PROPOSAL TO APPROVE THE REORGANIZATION AGREEMENT AND (II)  FOR THE PROPOSAL TO ADJOURN THE SPECIAL MEETING, IF NECESSARY OR ADVISABLE, TO PERMIT FURTHER SOLICITATION OF PROXIES.

Opinion of FBC’s Financial Advisor

In October 2014, FBC engaged Vining Sparks IBG, LP. (“Vining Sparks”) to render financial advisory and investment banking services to FBC. Vining Sparks agreed to assist FBC in assessing the fairness, from a financial point of view, of the merger consideration in the proposed merger to the shareholders of FBC. FBC selected Vining Sparks because Vining Sparks is a nationally recognized investment banking firm with substantial experience in transactions similar to the merger and is familiar with FBC and its business. As part of its investment banking business, Vining Sparks is continually engaged in the valuation of financial institutions and their securities in connection with mergers and acquisitions and other corporate transactions.

As part of its engagement, representatives of Vining Sparks participated in meetings of the FBC board of directors, at which the FBC board of directors evaluated the proposed merger. At these meetings, a Vining Sparks’ representative reviewed the financial aspects of the proposed merger and rendered an opinion that, as of April 1, 2015, the merger consideration offered to FBC’s shareholders in the merger was fair to the holders of FBC’s common stock from a financial point of view. The full text of Vining Sparks’ written opinion is attached asAppendix B to this proxy statement/prospectus and is incorporated herein by reference. FBC’s shareholders

are urged to carefully read the opinion in its entirety for a description of the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by Vining Sparks. The description of the opinion set forth below is qualified in its entirety by reference to the full text of such opinion.

For purposes of Vining Sparks’ opinion and in connection with its review of the proposed transaction, Vining Sparks has, among other things:

In performing its review, Vining Sparks has assumed and relied, without independent verification, upon the accuracy and completeness of all of the financial and other information that has been provided to it by FBC and First Financial and their respective representatives, and of the publicly available information that was reviewed by it. Vining Sparks did not make an independent evaluation or appraisal of the assets, or the liabilities (contingent or otherwise) of FBC or First Financial, nor was Vining Sparks furnished with any such evaluation or appraisal. Vining Sparks is not an expert in the evaluation of allowances for loan losses and did not review any individual credit files and did not make an independent evaluation of the adequacy of the allowance for loan losses, and has relied on and assumed that the allowance for loan losses set forth in the balance sheets of FBC and First Financial is adequate to cover such losses and complied fully with applicable law, regulatory policy and sound banking practice as of the date of such financial statements.

Vining Sparks’ opinion is necessarily based on economic, regulatory, market and other conditions as in effect on, and the information made available to Vining Sparks as of, the date of its opinion. Events occurring after the date thereof, including but not limited to, changes affecting the securities markets, the results of operations or material changes in the assets or liabilities of FBC or First Financial could materially affect the assumptions used in preparing the opinion. Vining Sparks assumed that all of the representations and warranties contained in the reorganization agreement and all related agreements are true and correct, that each party to such agreements will perform all of the covenants required to be performed by such party under such agreements and that the conditions precedent in the reorganization agreement are not waived.

No limitations were imposed by FBC’s board of directors upon Vining Sparks with respect to the investigations made or procedures followed in rendering its opinion. Vining Sparks’ opinion as expressed herein

is limited to the fairness, from a financial point of view, of the merger consideration to be received by the holders of FBC common stock in the merger and does not address FBC’s underlying business decision to proceed with the merger. Vining Sparks has been retained on behalf of the board of directors of FBC, and its opinion does not constitute a recommendation to any shareholder of FBC as to how such shareholder should vote at the special meeting with respect to the merger.

Vining Sparks relied upon the management of FBC as to the reasonableness of the financial and operating forecasts, and projections (and the assumptions and bases therefore) provided to or reviewed by Vining Sparks, and Vining Sparks assumed that such forecasts and projections reflect the best currently available estimates and judgments of FBC management. FBC does not publicly disclose internal management forecasts, projections or estimates of the type furnished to or reviewed by Vining Sparks in connection with its analysis of the financial terms of the proposed transaction, and such forecasts and estimates were not prepared with a view towards public disclosure. These forecasts and estimates were based on numerous variables and assumptions which are inherently uncertain and which may not be within the control of the management of FBC, including without limitation to, the general economic, regulatory and competitive conditions. Accordingly, actual results could vary materially from those set forth in such forecasts and estimates.

In rendering its opinion, Vining Sparks performed a variety of financial analyses. The following is a summary of the material financial analyses performed by Vining Sparks in connection with the preparation of its opinion and does not purport to be a complete description of all the analyses performed by Vining Sparks. The summary includes information presented in tabular format, which should be read together with the text that accompanies those tables. The preparation of a fairness opinion is a complex process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances. Therefore, an opinion is not necessarily susceptible to partial analysis or summary description. Vining Sparks believes that its analyses must be considered as a whole and that selecting portions of such analyses and the factors considered therein, without considering all factors and analyses, or attempting to ascribe relative weights to some or all such factors and analyses, could create an incomplete view of the evaluation process underlying its opinion. In its analyses, Vining Sparks made numerous assumptions with respect to industry performance, business and economic conditions, and other matters, many of which are beyond the control of FBC, First Financial and Vining Sparks. Any estimates contained in Vining Sparks’ analyses are not necessarily indicative of future results or values, which may be significantly more or less favorable than such estimates. Estimates of values of companies do not purport to be appraisals or necessarily reflect the prices at which companies or their securities may actually be sold.

Summary of Proposal. Vining Sparks reviewed the financial terms of the proposed transaction. As discussed elsewhere in this proxy statement/prospectus, the FBC common stock will be converted into the right to receive the merger consideration pursuant to the terms of the reorganization agreement. If the FBC’s consolidated shareholders’ equity as of the close of business on the business day immediately preceding the closing date of the merger, after certain adjustments prescribed by the reorganization agreement have been made, is less than $14,705,000, then the merger consideration will be reduced on a dollar-for-dollar basis by the amount of such difference. As indicated in the reorganization agreement, FBC may dividend the excess amount if FBC’s consolidated shareholders’ equity exceeds $14,705,000. Additionally, First Financial has also agreed to redeem all of FBC’s Subordinated Promissory Notes due June 30, 2028 within three business days of the closing date of the merger. FBC’s Subordinated Promissory Notes due June 30, 2028 had an aggregate outstanding principal balance of $13,125,000 as of April 1, 2015. The total value of the merger consideration would have a minimum price of $57.0 million and a maximum price of $61.0 million. The number of shares of First Financial common stock deliverable for each share of FBC common stock will be determined based on the average daily closing price of First Financial’s common stock on the NASDAQ Global Select Market for each of the twenty consecutive trading days ending on the fifth business day immediately preceding the closing date of the merger.

Based on merger consideration of $59.0 million and a closing price of $26.80 at March 9, 2015, First Financial would issue 2,201,493 shares of First Financial common stock to the holders of shares of common

stock of FBC. Based on 884,600 shares of FBC common stock outstanding (which includes the exercise of all options), each share of FBC common stock would be converted into 2.4887 shares of First Financial common stock. Merger consideration of $59.0 million represents a price to required equity of $14,705,000 of 4.01x, a price to required tangible equity of 4.06x, a price to 2014 earnings of 16.23x, a price to assets of 15.87% and a tangible premium on core deposits of 14.92%.

Analysis of Selected Public Companies. Vining Sparks used publicly available information to compare selected financial and market trading information for First Financial with those of a group of comparable publicly traded Texas banking organizations with total assets between $3 and $30 billion and a return on assets greater than 0.00%. The companies in First Financial’s peer group were as follows:

To perform this analysis, Vining Sparks used financial information as of December 31, 2014, a price of $26.80 for First Financial (the closing price on March 9, 2015) and pricing data for the peer group as of March 9, 2015 obtained from SNL Financial LC. The following table sets forth the comparative financial and market data:

Stock Trading History. Vining Sparks reviewed the closing per share market prices and volumes for First Financial common stock which is which is listed for trading on The NASDAQ Global Select Market under the symbol “FFIN” on a daily basis from March 10, 2014 to March 9, 2015.

For the period between March 10, 2014 and March 9, 2015, the closing price of First Financial common stock ranged from a low of $24.46 to a high of $32.54. The average closing price for the period was $29.12, the closing price on March 9, 2015 was $26.80 per share and the average daily trading volume for First Financial was 211,968 shares.

Analysis of Selected Bank Merger Transactions. Vining Sparks reviewed certain publicly available information regarding selected merger and acquisition transactions (the “Comparable Transactions”) announced from January 1, 2013 to March 9, 2015 involving Texas financial institutions with total assets between $25 million and $5 billion and a return on assets greater than 0.50%. The transactions included in the group are shown on the following chart. This data was obtained from SNL Financial LC.

Vining Sparks reviewed the multiples of transaction value to stated book value, transaction value to tangible book value, transaction value to last twelve months earnings and tangible book premium to core deposits and calculated high, low, mean and median multiples for the Comparable Transactions. The median multiples were then applied to FBC’s required equity, earnings for 2014 and FBC’s assets and core deposits as of December 31, 2014 to derive an implied range of values of FBC. The following table sets forth the median multiples as well as the implied values based upon those median multiples.

The transaction value of $59.0 million is within the range of implied values computed in using the Comparable Transactions, which supports the fairness of the transaction. No company or transaction used as a comparison in the above analysis is identical to FBC or the merger. Accordingly, an analysis of these results is not strictly mathematical. An analysis of the results of the foregoing involves complex considerations and judgments concerning differences in financial and operating characteristics of FBC and the companies included in the Comparable Transactions.

Present Value Analysis. Vining Sparks calculated the present value of theoretical future earnings of FBC and compared the transaction value to the calculated present value of FBC’s common stock on a stand-alone

basis. Based on projected earnings for FBC for 2015 through 2019, and a discount rate of 12%, and including a residual value, the stand-alone present value of FBC equaled $51.8 million. The transaction value of $59.0 million is above this value, which supports the fairness of the transaction.

Discounted Cash Flow Analysis.Using a discounted cash flow analysis, Vining Sparks estimated the net present value of the future streams of after-tax cash flow that FBC could produce to benefit a potential acquiror, referred to as dividendable net income, and added a terminal value. Based on projected earnings for FBC for 2015 through 2019, Vining Sparks assumed after-tax distributions to a potential acquiror such that its tier 1 leverage ratio would be maintained at 7.00%. The terminal values for FBC were calculated based on FBC’s projected 2019 equity and earnings, the median price to book and median price to earnings multiples paid in the Comparable Transactions and utilized discount rate of 12%. This discounted cash flow analysis indicated implied values of $36.5 million and $56.0 million. The transaction value of $59.0 million is above these values, which supports the fairness of the transaction.

In the two years prior to the issuance of this opinion, Vining Sparks has not had a material relationship with FBC or First Financial where compensation was received or that it contemplates will be received after closing of the transaction. Pursuant to the terms of an engagement letter with FBC, Vining Sparks will receivereceived a fee of $50,000 upon delivery of its opinion. Vining Sparks’ fee iswas not contingent upon consummation of the merger. In addition, FBC has agreed to indemnify Vining Sparks against certain liabilities and expenses arising out of or incurred in connection with its engagement, including liabilities and expenses which may arise under the federal securities laws.

First Financial’s Reasons for the Merger

As a part of First Financial’s growth strategy, First Financial routinely evaluates opportunities to acquire financial institutions. The acquisition of FBC and its wholly-owned subsidiary First Bank is consistent with First Financial’s expansion strategy. First Financial’s board of directors, senior management and certain lenders reviewed the business, financial condition, results of operation and prospects for First Bank, the market condition of the market area in which First Bank conducts business, the compatibility of the management and the proposed financial terms of the transaction. In addition, management of First Financial believes that the transaction will expand First Financial’s footprint in the Conroe and the southeast Texas area, provide opportunities for future growth and provide the potential to realize cost savings. First Financial’s board of directors also considered the financial condition and valuation for both FBC and First Financial as well as the financial and other effects the transaction would have on First Financial’s shareholders.

While management of First Financial believes that revenue opportunities will be achieved and costs savings will be obtained following the transaction, First Financial has not quantified the amount of enhancements or projected the areas of operation in which such enhancements will occur.

In view of the variety of factors considered in connection with its evaluation of the transaction, the First Financial board did not find it useful to and did not attempt to quantify, rank or otherwise assign relative weights to factors it considered. Further, individual directors may have given differing weights to different factors. In addition, the First Financial board did not undertake to make any specific determination as to whether any particular factor, or any aspect of any particular factor, was favorable or unfavorable to its ultimate determination. Rather, the board conducted an overall analysis of the factors it considered material, including thorough discussions with, and questioning of, First Financial’s management.

Effective Time of the Merger

The merger will become effective at the date and time specified in the certificate of merger to be filed with the Secretary of State of the State of Texas regarding the merger. If the shareholders of FBC approve the merger pursuant to the reorganization agreement at the special meeting, and if all required regulatory approvals are

obtained and the other conditions to the parties’ obligations to effect the merger are met or waived by the party entitled to do so, we anticipate that the merger will be completed in July 2015, although delays could occur. We cannot assure you that we can obtain the necessary shareholder and regulatory approvals or that the other conditions to completion of the merger set forth in the reorganization agreement can or will be satisfied.

Exchange of FBC Stock Certificates

Promptly after the effective time of the merger, First Financial will deposit with or make available to Continental Stock Transfer & Trust Company, as exchange and transfer agent, shares of First Financial common stock and cash to be exchanged for shares of FBC common stock in accordance with the reorganization agreement (the “Exchange Fund”). With the intent to be within five days of the effective time of the merger, First Financial will cause the exchange agent to mail to each record holder of FBC common stock a letter of transmittal and instructions describing the procedures for surrendering stock certificates representing shares of FBC common stock in exchange for shares of First Financial common stock and, if applicable, cash. The shares of First Financial common stock issuable in exchange for the shares of FBC common stock will be issued solely in uncertificated book-entry form. Please do not send the exchange agent any stock certificates until you receive these instructions. Stock certificates delivered to the exchange agent without a properly completed letter of transmittal will be rejected and returned for corrective action.

Until surrendered in accordance with the instructions of the exchange agent, other than shares of FBC common stock subject to the exercise of dissenters’ rights, each stock certificate representing shares of FBC common stock will represent after the effective time of the merger only the right to receive, without interest, the merger consideration and any cash in lieu of a fractional share of First Financial common stock to be issued or paid upon surrender of such stock certificate and any dividends or distributions to which such holder is entitled pursuant to the reorganization agreement. Subject to the terms of the reorganization agreement, each record holder of FBC common stock will generally be entitled to receive without interest, the amount of dividends or other distributions with a record date after the effective time of the merger that are payable with respect to whole shares of First Financial common stock.

If any certificate representing shares of FBC common stock is lost, stolen or destroyed, upon the making of an affidavit of such fact by the person claiming the certificate to be lost, stolen or destroyed and, if required by First Financial or the exchange agent, the posting by such person of a bond in such amount as the exchange agent may determine is reasonably necessary as indemnity against any claim that may be made against it with respect to such certificate, the exchange agent will issue in exchange for the lost, stolen or destroyed certificate the merger consideration, cash in lieu of fractional shares and any dividends or other distributions that have been payable or become payable in respect of the shares of First Financial common stock represented by that certificate pursuant to the reorganization agreement.

Any portion of the Exchange Fund that remains unclaimed by the shareholders of FBC at the expiration of six months after the effective time of the merger will be paid to First Financial. In such event, any former shareholders of FBC who have not previously complied with the exchange procedures set forth in the reorganization agreement and instructions from the exchange agent will look only to First Financial with respect to the merger consideration, any cash in lieu of any fractional shares and any unpaid dividends and distributions on the First Financial common stock as determined pursuant to the reorganization agreement, in each case, without any interest.

First Financial and the exchange agent, as the case may be, will be entitled to deduct and withhold, if necessary, from any consideration payable pursuant to the reorganization agreement to any holder of FBC common stock such amounts as First Financial or the exchange agent is required to deduct or withhold under applicable tax laws, and any such withheld amounts that are paid to the appropriate taxing authorities will be treated for purposes of the reorganization agreement as having been paid to the holder of FBC common stock from whom such amounts were deducted or withheld.

Conduct of Business Pending Effective Time

From the date of the reorganization agreement to and including the closing date of the merger, unless otherwise permitted in writing by First Financial, FBC will, and will cause First Bank to:

From the date of the reorganization agreement to closing, unless permitted by the reorganization agreement or First Financial consents in writing, FBC will not, and will not allow First Bank to:

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consistent with past practices, and bonuses, commissions, and incentives consistent with past and normal First Bank practices to First Bank employees and officers, except that FBC and First Bank, shall be permitted to (i) pay all bonus amounts that are accrued for the benefit of officers of First Bank in accordance with past and normal First Bank practices from January 1, 2015 through the last calendar day of the month immediately preceding the month in which the closing occurs, and (ii) contribute to First Bank’s 401(k) profit sharing plan all amounts that are accrued for the benefit of participants in such plan in accordance with past and normal Bank practices from January 1, 2015 through the last calendar day of the month immediately preceding the month in which the closing occurs;

For a complete description of such restrictions on the conduct of the business of FBC, we refer you to the reorganization agreement, which is attached asAppendix Ato this proxy statement/prospectus.

No Solicitation

FBC agreed that neither it, nor First Bank, nor any of their respective directors or officers will take any action to:

FBC and First Bank agreed to notify First Financial in writing within one business day after receipt of any unsolicited inquiries or acquisition proposals.

Conditions to Completion of the Merger

The reorganization agreement contains a number of conditions to the obligations of First Financial and FBC to complete the merger which must be satisfied as of the closing date of the merger, including, but not limited to, the following:

In addition to the conditions listed above, First Financial’s obligation to complete the merger is subject to the satisfaction of the following conditions:

Any condition to the completion of the merger, except the required shareholder and regulatory approvals, and the absence of an order or ruling prohibiting the merger, may be waived in writing by the party to the reorganization agreement entitled to the benefit of such condition. We cannot be certain when or if the conditions to the merger will be satisfied or waived, or that the merger will be completed.

Additional Agreements

In addition to the agreements described above, First Financial and FBC each agreed in the reorganization agreement to take certain other actions, including but not limited to:

FBC agreed in the reorganization agreement to take certain other actions, including, but not limited to:

First Financial agreed in the reorganization agreement to take certain other actions, including, but not limited to:

Representations and Warranties of FBC and First Financial

In the reorganization agreement, FBC has made representations and warranties to First Financial, and First Financial has made representations and warranties to FBC. The more significant of these relate to (among other things):

FBC also has made additional representations and warranties to First Financial with respect to (among other things):

First Financial has also made additional representations and warranties to FBC with respect to (among other things) its compliance with its SEC reporting obligations and the accuracy of such reports.

Financial Interests of Directors and Officers of FBC in the Merger

In considering the recommendation of the board of directors of FBC to vote for the proposal to approve the reorganization agreement, you should be aware that certain directors and officers of FBC have interests in the merger that are in addition to, or different from, their interests as shareholders of FBC. The board of FBC was aware of these interests and considered them in approving the reorganization agreement. These interests include:

In the event that an employee’s employment is terminated without cause or for good reason (as such terms are defined in the employment agreements), the employee will be entitled to receive his accrued benefits and, subject to certain conditions, if such termination occurs less than two years following the closing date of the merger, the employee will be entitled to receive the base salary the employee would have earned from the date of termination through the end of the second year following the closing date of the merger. The employment agreements also contain provisions for certain payment in the event of the employee’s death or permanent disability. Each employment agreement has been executed but will not become effective until the effective time of the merger.

NASDAQ Listing

First Financial agreed to file with NASDAQ Global Select Market all documents with respect to the listing of the shares of First Financial common stock to be issued in the merger.

Amendment or Waiver of the Reorganization Agreement

No termination, cancellation, modification, amendment, deletion, addition or other change to the reorganization agreement, or any provision thereof, or waiver of any right or remedy therein provided, is effective for any purpose unless specifically set forth in a writing signed by the party or parties to be bound therein. The waiver of any right or remedy in respect to any occurrence or event on one occasion is not deemed a waiver of such right or remedy in respect to such occurrence or event on any other occasion.

The reorganization agreement may be amended at any time prior to or after approval of the reorganization agreement by the shareholders of FBC but, after any submission of the reorganization agreement to such shareholders for approval, no amendment of the reorganization agreement will be made that reduces the consideration payable to FBC or that materially and adversely affects the rights of shareholders of FBC under the reorganization agreement without the requisite approval of such shareholders.

Termination of the Reorganization Agreement

First Financial and FBC can mutually agree at any time to terminate the reorganization agreement without completing the merger. In addition, either First Financial or FBC may decide, without the consent of the other, to terminate the reorganization agreement if:

In addition, First Financial may terminate the reorganization agreement, without the consent of FBC, if:

Expenses

FBC and First Financial will each pay their respective expenses incurred in connection with the preparation and performance of their respective obligations under the reorganization agreement, whether or not the transactions provided for in the reorganization agreement are completed, including, but not limited to, fees and expenses of their own counsel, financial or other consultants, investment bankers and accountants, and filing, registration, application and printing fees. Similarly, each of FBC and First Financial agreed to indemnify the other party against any cost, expense or liability (including reasonable attorneys’ fees) in respect of any claim made by any party for a broker’s or finder’s fee in connection with the merger.

Material U.S. Federal Income Tax Consequences of the Merger

The following discussion addresses the material U.S. federal income tax consequences of the merger to U.S. holders (as defined below) of FBC common stock. The discussion is based on the Code, Treasury regulations, administrative rulings and judicial decisions, all as currently in effect and all of which are subject to change (possibly with retroactive effect) and to differing interpretations. Accordingly, the U.S. federal income tax consequences of the merger to holders of FBC common stock could differ from those described below.

This discussion applies only to U.S. holders that hold their FBC common stock as a capital asset within the meaning of Section 1221 of the Code. Further, this discussion does not address all aspects of U.S. federal taxation that may be relevant to a particular U.S. holder in light of the holder’s personal circumstances or to holders subject to special treatment under U.S. federal income tax laws, including, without limitation:

In addition, the discussion does not address any alternative minimum tax or any state, local or foreign tax consequences of the merger, or any tax consequences of the merger under any U.S. federal tax laws other than income tax.

For purposes of this discussion, a U.S. holder is a beneficial owner of FBC common stock who is, for U.S. federal income tax purposes: (i) an individual who is a citizen or resident of the United States; (ii) a corporation or other entity taxable as a corporation created or organized under the laws of the United States or any state thereof or the District of Columbia; (iii) an estate that is subject to U.S. federal income tax on its income regardless of its source; or (iv) a trust (A) if a U.S. court is able to exercise primary supervision over its administration and one or more U.S. persons have the authority to control all substantial decisions of the trust or (B) that was in existence on August 20, 1996, and has made a valid election to be treated as a United States person for U.S. federal income tax purposes.

If a partnership (or an entity or arrangement treated as a partnership for U.S. federal income tax purposes) holds shares of FBC common stock, the U.S. federal income tax treatment of a partner in such partnership will depend upon the status of the partner and the activities of the partnership. We urge such partners and partnerships to consult their own tax advisors regarding the particular tax consequences of the merger to them.

Determining the actual U.S. federal income tax consequences of the merger to a holder may be complex and will depend, in part, on the holder’s particular circumstances. We urge each holder of FBC common stock to consult his or her tax advisor with respect to the particular tax consequences of the merger to such holder.

U.S. Federal Income Tax Consequences of the Merger Generally

NeitherIn connection with the filing with the SEC of this registration statement on Form S-4 of which this proxy statement/prospectus is a part, Norton Rose Fulbright US LLP, counsel to First Financial, nor FBC has requested anrendered its tax opinion of counsel addressing the qualification ofto First Financial: (a) that the merger asis a reorganization within the meaning of Section 368(a) of the Code.Code and that (b) that the following discussion under the heading “Material U.S. Federal Income Tax Consequences of the Merger,” insofar as it relates to U.S. federal income tax law, is accurate in all material respects. A copy of this opinion has been filed as an exhibit to First Financial’s registration statement of which this proxy statement/prospectus is a part. In addition, norendering its opinion, counsel has relied upon certain assumptions and representation and covenants, including those contained in certificates of officers of First Financial and FBC, reasonably satisfactory in form and substance to counsel. If any of the assumptions, representations or covenants upon which counsel’s opinion is based are inaccurate, the U.S. federal income tax consequences of the merger could be adversely affected. The opinion represents counsel’s best legal judgment. No ruling has been requested (or is expected to be requested) from the IRS regarding the U.S. federal income tax consequences of the merger.merger and counsel’s opinion is not binding on the IRS. Accordingly, there can be no assurance that the IRS will not assert, and a court will not sustain, a position contrary to any of the tax consequences set forth below. The following discussion regarding the U.S. federal income tax consequences of the merger assumes that the merger will be consummated as described in the reorganization agreement and this proxy statement/prospectus and will qualify as a reorganization within the meaning of Section 368(a) of the Code.prospectus.

Exchange Solely for First Financial Common Stock. No gain or loss will be recognized by a U.S. holder who receives solely shares of First Financial common stock (except for cash received in lieu of a fractional share)

in exchange for all of his or her shares of FBC common stock. The tax basis of the shares of First Financial common stock received by a U.S. holder in such exchange will be equal (except for the basis attributable to any fractional share of First Financial common stock) to the basis of the FBC common stock surrendered in exchange for the First Financial common stock. The holding period of the First Financial common stock received by a U.S. holder will include the holding period of shares of FBC common stock surrendered by the holder in exchange for the First Financial common stock. If a U.S. holder purchased or acquired his or her FBC common stock on different dates or at different prices, the U.S. holder should consult his or her tax advisor regarding the tax basis and holding period of the First Financial common stock received in the merger.

Exchange for First Financial Common Stock and Cash. A U.S. holder who receives both First Financial common stock and cash in the exchange will recognize gain (but not loss) equal to the lesser of (1) the amount of cash received (other than cash received in lieu of a fractional share of First Financial common stock) and (2) the amount of gain “realized” in the transaction. The amount of gain a U.S. holder “realizes” will equal the amount by which the cash plus the fair market value of First Financial common stock received exceeds the holder’s adjusted tax basis in the FBC common stock to be surrendered in the exchange. Any gain recognized by a U.S. holder could be taxed as a capital gain or a dividend, as described below. Except to the extent any cash received is treated as a dividend as discussed below, any gain recognized generally will be long-term capital gain if, as of the effective date of the merger, the U.S. holder’s holding period with respect to the FBC common stock surrendered exceeds one year.

If a U.S. holder acquired his or her FBC common stock at different times or different prices, the holder should consult the holder’s tax advisor regarding the manner in which gain or loss should be determined for each identifiable block of FBC common stock surrendered in the exchange.

The aggregate tax basis of the shares of First Financial common stock received (including a fractional share of First Financial common stock deemed issued and redeemed as described below) by a U.S. holder will be the same as the basis of the shares of FBC common stock surrendered in exchange for the shares of First Financial common stock, plus any gain recognized in the merger by such holder (excluding gain as a result of cash received in lieu of a fractional share) regardless of whether such gain is classified as capital gain or dividend income, and minus any cash received (other than cash in lieu of a fractional share) by the holder in the merger. The holding period for shares of First Financial common stock received in the merger (including a fractional share of First Financial common stock deemed received and redeemed as described below) by a U.S. holder will include such holder’s holding period for the FBC common stock surrendered in exchange for the First Financial common stock. If a U.S. holder purchased or acquired FBC common stock on different dates or at different prices, the holder should consult his or her tax advisor for purposes of determining the basis and holding period of the First Financial common stock received in the merger.

Cash Received in Lieu of a Fractional Share. A U.S. holder who receives cash instead of a fractional share of First Financial common stock will be treated as having received the fractional share in the merger and then as having exchanged the fractional share for cash in redemption by First Financial. A U.S. holder will generally recognize gain or loss equal to the difference between the amount of cash received and the tax basis allocable to a fractional share. The gain or loss will be capital gain or loss and long-term capital gain or loss if the holder has held the fractional share exchanged (including the holding period for the FBC common stock exchanged therefor) for more than one year at the effective date of the merger. The deductibility of capital losses is subject to limitations.

Potential Characterization of Gain as a Dividend. In general, the determination of whether gain recognized by a U.S. holder who exchanges his or her FBC common stock for a combination of First Financial common stock and cash will be treated as capital gain or as a dividend will depend on whether, and to what extent, the merger reduces the U.S. holder’s deemed percentage ownership of First Financial common stock. For purposes of this determination, a U.S. holder will be treated as if the holder first exchanged his or her FBC common stock solely for First Financial common stock and then First Financial immediately redeemed a portion of the holder’s First Financial common stock in the exchange for cash received in the merger by that holder. The gain

recognized by the U.S. holder in the exchange followed by a deemed redemption will be capital gain if, with respect to such holder, the deemed redemption is “substantially disproportionate” or “not essentially equivalent to a dividend.”

In general, the deemed redemption will be “substantially disproportionate” with respect to a U.S. holder if the percentage described in clause (2) below is less than 80% of the percentage described in clause (1) below. Whether the deemed redemption is “not essentially equivalent to a dividend” with respect to a U.S. holder will

depend on the holder’s particular circumstances. In order for the deemed redemption to be “not essentially equivalent to a dividend”, the reduction must result in a “meaningful reduction” in the holder’s deemed percentage ownership of First Financial common stock. In general, a determination requires a comparison of (1) the percentage of outstanding voting stock of First Financial that the holder is deemed actually and constructively to have owned immediately before the deemed redemption by First Financial and (2) the percentage of outstanding voting stock of First Financial actually and constructively owned by the U.S. holder immediately after the deemed redemption by First Financial. In applying the foregoing test, a U.S. holder may, under constructive ownership rules, be deemed to own stock in addition to stock actually owned by the U.S. holder, including stock owned by other persons and stock subject to an option held by such holder or by other persons. Because the constructive ownership rules are complex, each U.S. holder should consult his or her own tax advisor as to the applicability of these rules. The IRS has indicated that a minority shareholder in a publicly traded corporation whose relative stock interest is minimal and who exercises no control with respect to corporate affairs is considered to have a meaningful reduction if that shareholder has any reduction in his or her percentage stock ownership under the foregoing analysis.

These rules are complex and dependent upon the specific facts of a particular U.S. holder. Consequently, we urge each U.S. holder that may be subject to these rules to consult his or her own tax advisor as to the application of these rules to the particular facts relevant to the holder.

Dissenters.Upon the proper exercise of dissenters’ rights, a U.S. holder will exchange all of the shares of FBC common stock actually owned by that holder solely for cash and will recognize gain or loss equal to the difference between the amount of cash received and his or her adjusted tax basis in the shares of FBC common stock surrendered. The gain or loss will be long-term capital gain or loss if the U.S. holder’s holding period with respect to the FBC common stock surrendered is more than one year. The deductibility of capital losses is subject to limitations. In some cases, if the holder owns shares of First Financial common stock actually or constructively after the merger, the cash received could be treated as a dividend, in which case such holder may recognize dividend income up to the amount of cash received.

Medicare Tax. If a U.S. holder that is an individual has modified gross income for the taxable year over a certain threshold (between $125,000 and $250,000 depending upon the individual’s U.S. federal income tax filing status), such an individual is subject to a 3.8% tax on the lesser of: (i) his or her “net investment income” for the relevant taxable year; or (ii) the excess of his or her modified gross income for the taxable year over his or her applicable threshold (between $125,000 and $250,000 depending upon the individual’s U.S. federal income tax filing status). Net investment income generally would include any capital gain incurred in connection with the merger (including gain treated as dividend income), as well as other items of interest, dividends, capital gains, and rental or royalty income of the individual.

Backup Withholding

Payments of cash to a U.S. holder pursuant to the merger may under certain circumstances be subject to information reporting and backup withholding. Generally, backup withholding will not apply if a U.S. holder:

Any amounts withheld under the backup withholding rules are not an additional tax and will generally be allowed as a refund or credit against a holder’s U.S. federal income tax liability, provided the holder furnishes the required information to the IRS.

Reporting Requirements

A holder who receives shares of First Financial common stock upon completion of the merger and who is considered a “significant holder” will be required to retain records pertaining to the merger and to file with such holder’s U.S. federal income tax return for the year in which the merger takes place a statement setting forth certain facts relating to the merger. For this purpose, a holder is only a significant holder if the person owns at least 1% by vote or value of FBC’s outstanding shares or has a tax basis of $1,000,000 or more in his or her FBC common stock and securities. Such statement must include the holder’s tax basis in and fair market value of his or her FBC common stock and securities surrendered in the merger.

Tax Treatment of Entities

No gain or loss should be recognized by First Financial or FBC as a result of the merger.

This discussion of certain material U.S. federal income tax consequences is for general information only and is not tax advice. We urge holders of FBC common stock to consult their tax advisors with respect to the application of U.S. federal income tax laws to their particular situations as well as any tax consequences arising under the U.S. federal estate or gift tax rules, or under the laws of any state, local, foreign or other taxing jurisdiction or under any applicable tax treaty.

Accounting Treatment

The merger will be accounted for under the acquisition method of accounting under accounting principles generally accepted in the United States of America. Under this method, FBC’s assets and liabilities as of the date of the merger will be recorded at their respective fair values. Any difference between the purchase price for FBC and the fair value of the identifiable net assets acquired (including core deposit intangibles) will be recorded as goodwill. In accordance with ASC Topic 805,Business Combinations, issued in July 2001, the goodwill resulting from the merger will not be amortized to expense, but instead will be reviewed for impairment at least annually and to the extent goodwill is impaired, its carrying value will be written down to its implied fair value and a charge will be made to earnings. Core deposit and other intangibles with definite useful lives recorded by First Financial in connection with the merger will be amortized to expense in accordance with such rules. The consolidated financial statements of First Financial issued after the merger will reflect the results attributable to the acquired operations of FBC beginning on the date of completion of the merger.

Restrictions on Resales of First Financial Common Stock Received in the Merger

The shares of First Financial common stock issued in the merger will not be subject to any restrictions on transfer arising under the Securities Act of 1933, as amended, referred to in this proxy statement/prospectus as the “Securities Act,” except for shares of First Financial common stock issued to any FBC shareholder who may be deemed to be an “affiliate” of First Financial after completion of the merger. “Affiliates” generally are defined as persons or entities who control, are controlled by or are under common control with First Financial at or after the effective time of the merger and generally include executive officers, directors and beneficial owners of 10% or more of the common stock of First Financial. FBC shareholders who are not affiliates of First Financial after the completion of the merger may sell their shares of First Financial common stock at any time.

To the knowledge of FBC, no FBC shareholder who receives First Financial common stock will be deemed to be an affiliate of First Financial upon completion of the merger. In the event a FBC shareholder become an affiliates of First Financial after completion of the merger, any sales of First Financial common stock will be

subject to the volume and sale limitations of Rule 144 under the Securities Act, until such former FBC Shareholder is no longer an affiliate of First Financial. This proxy statement/prospectus does not cover resales of First Financial common stock received by any person upon completion of the merger, and no person is authorized to make any use of this proxy statement/prospectus in connection with any resale.

Regulatory Approvals Required for the Merger

First Financial’s acquisition of FBC must be approved by the Federal Reserve. On April 10, 2015, First Financial filed the required application with the Federal Reserve Bank of Dallas to request the Federal Reserve’s approval under the BHC Act.Act, which the Federal Reserve approved on May 20, 2015.

In addition, the bank merger of First Bank with and into First Financial Bank requires the approval of the OCC. On April 10, 2015, First Financial Bank and First Bank filed an application with the OCC to obtain approval of bank merger.merger, which the OCC approved on May 22, 2015. The U.S. Department of Justice will havehas between 15 and 30 days following approval by the OCC to challenge the approval on antitrust grounds. While FBC and First Financial do not know of any reason that the Department of Justice would challenge regulatory approval by the OCC and believe that the likelihood of such action is remote, there can be no assurance that the Department of Justice will not initiate such a proceeding, or if such a proceeding is initiated, as to the result of any such challenge.

The merger cannot proceed in the absence of these required regulatory approvals. The approval of any notice or application merely implies satisfaction of regulatory criteria for approval, and does not include review of the merger from the standpoint of the adequacy of the consideration to be received by, or fairness to, shareholders. Regulatory approval does not constitute an endorsement or recommendation of the proposed transaction.

We cannot assure you as to whether or when the requisite regulatory approvals will be obtained, and, if obtained, we cannot assure you as to the date of receipt of any of these approvals, the terms thereof or the absence of any litigation challenging them. Likewise, we cannot assure you that the Department of Justice or a state attorney general will not attempt to challenge the merger on antitrust grounds, or, if such a challenge is made, as to the result of that challenge.

First Financial and FBC are not aware of any material governmental approvals or actions that are required prior to the parties’ completion of the merger other than those described in this proxy statement/prospectus. If any additional governmental approvals or actions are required, the parties presently intend to seek those approvals or actions. However, the parties cannot assure you that any of these additional approvals or actions will be obtained.

Although the approval of the Texas Department of Banking is not required for the merger of First Bank with and into First Financial Bank, a copy of the application filed with the Federal Reserve was filed with the Texas Department of Banking on April 23, 2015, which the Texas Department of Banking acknowledged complied with the applicable statutes of Texas law on May 19, 2015.

Dissenters’ Rights of FBC Shareholders

General. If you hold one or more shares of FBC common stock, you are entitled to dissenters’ rights under Texas law and have the right to dissent from the merger and have the appraised fair value of your shares of FBC common stock paid to you in cash. The appraised fair value may be more or less than the value of the shares of First Financial common stock and, if applicable, cash, being paid in the merger in exchange for the common stock of FBC. If you are contemplating exercising your right to dissent, we urge you to read carefully the provisions of Chapter 10, Subchapter H of the TBOC, which are attached to this proxy statement/prospectus asAppendix C, and consult with your legal counsel before electing or attempting to exercise these rights. The following discussion describes the steps you must take if you want to exercise your right to dissent. You should read this summary and the full text of the law carefully.

How to Exercise and Perfect Your Right to Dissent. To be eligible to exercise your right to dissent to the merger:

(ii)

you must vote your shares of FBC common stock against approval of the reorganization agreement at the special meeting in person or by proxy; and

If you intend to dissent from the merger, you should send the notice to:

FBC Bancshares, Inc.

1800 West White Oak Terrace

Conroe, Texas 77304

Attention: President and Secretary

If you fail to (i) send the written objection to the merger in the proper form prior to the FBC special meeting, (ii) vote your shares of FBC common stock at the special meeting against the approval of the reorganization agreement or (iii) submit your demand for payment in the proper form on a timely basis, you will lose your right to dissent from the merger. If you fail to submit to First Financial on a timely basis the certificates representing the shares of FBC common stock that you hold after you have submitted the demand for payment as described above, First Financial will have the option to terminate your right of dissent as to your shares of FBC common stock. In any instance of a termination or loss of your right of dissent, you will instead receive the consideration authorized by the board of directors of FBC and calculated in accordance with the reorganization agreement following consummation of the merger. If you comply with items (i) and (ii) above and the merger is completed, First Financial will send you a written notice advising you that the merger has been completed. First Financial must deliver this notice to you within ten days after the merger is completed.

Your Demand for Payment. If the merger is completed, you have provided your written objection to the merger to FBC in a timely manner and in proper form and you have voted against the reorganization agreement at the special meeting as described above and you desire to receive the fair value of your shares of FBC common stock in cash, you must, within 20 days of the date on which First Financial sends to you the notice of the effectiveness of the merger, give First Financial a written demand for payment of the fair value of your shares of FBC common stock. The fair value of your shares of FBC common stock will be the value of the shares on the day immediately preceding the merger, excluding any appreciation or depreciation in anticipation of the merger. After the merger is completed, your written demand and any notice sent to First Financial must be addressed to:

First Financial Bankshares, Inc.

400 Pine Street

Abilene, Texas 79601

Attention: President and Secretary

Your written demand must include a demand for payment for your shares for which rights of dissent and appraisal are sought and must state the number of shares and class of FBC common stock you own and your estimate of the fair value of your shares of FBC common stock and an address to which a notice relating to the

dissent and appraisal procedures may be sent. This written demand must be delivered to First Financial within 20 days of the date on which First Financial sends to you the notice of the effectiveness of the merger. If your written demand for payment in proper form is not received by First Financial within that 20 day period, you will be bound by the merger and you will not be entitled to receive a cash payment representing the fair value of your shares of FBC common stock. Instead, you will receive shares of First Financial common stock and, if applicable, cash as the merger consideration set forth in the reorganization agreement.

Delivery of Stock Certificates.If you have satisfied the requirements for the exercise of your right to dissent described above, including the delivery of the written demand for payment to First Financial as described above, you must, not later than the 20th day after you make your written demand for payment to First Financial, submit to First Financial your certificate or certificates representing the shares of FBC common stock that you own, as the case may be. You may submit those certificates with your demand for payment if you prefer. In accordance with the provisions of the TBOC, First Financial will note on each such certificate that you have demanded payment of the fair value of the shares of FBC common stock that were represented by such certificate under the provisions of the TBOC relating to the rights of dissenting owners. If you fail to submit all of the certificates representing the shares of FBC common stock for which you have exercised the right of dissent in a timely fashion, First Financial will have the right to terminate your rights of dissent and appraisal with respect to all of your shares of FBC common stock unless a court, for good cause shown, directs First Financial not to terminate those rights.

First Financial’s Actions Upon Receipt of Your Demand for Payment. Within 20 days after First Financial receives your demand for payment and your estimate of the fair value of your shares of FBC common stock, First Financial must send you written notice stating whether or not it accepts your estimate of the fair value of your shares.

If First Financial accepts your estimate, First Financial will notify you that it will pay the amount of your estimated fair value within 90 days of the merger being completed. First Financial will make this payment to you only if you have surrendered the share certificates representing your shares of FBC common stock, duly endorsed for transfer, to First Financial.

If First Financial does not accept your estimate, First Financial will notify you of this fact and will make an offer of an alternative estimate of the fair value of your shares that it is willing to pay you within 120 days of the merger being completed, which you may accept within 90 days or decline.

Payment of the Fair Value of Your Shares of FBC Common Stock Upon Agreement of an Estimate. If you and First Financial have reached an agreement on the fair value of your shares of FBC common stock within 90 days after the merger is completed, First Financial must pay you the agreed amount within 120 days after the merger is completed, provided that you have surrendered the share certificates representing your shares of FBC common stock, duly endorsed for transfer, to First Financial.

Commencement of Legal Proceedings if a Demand for Payment Remains Unsettled. If you and First Financial have not reached an agreement as to the fair market value of your shares of FBC common stock within 90 days after the merger is completed, you or First Financial may, within 60 days after the expiration of such 90 day period, commence proceedings in Taylor County, Texas, asking the court to determine the fair value of your shares of FBC common stock. The court will determine if you have complied with provisions of the TBOC regarding their right of dissent and if you have become entitled to a valuation of and payment for your shares of FBC common stock. The court will appoint one or more qualified persons to act as appraisers to determine the fair value of your shares in the manner prescribed by the TBOC. The appraisers will determine the fair value of your shares and will report this value to the court. The court will consider the report, and both you and First Financial may address the court about the report. The court will determine the fair value of your shares and direct First Financial to pay that amount, plus interest, which will begin to accrue 91 days after the merger is completed. The court may require you to share in the court costs relating to the matter to the extent the court deems it fair and equitable that you do so.

Rights as a Shareholder. If you have made a written demand on First Financial for payment of the fair value of your shares of FBC common stock, you will not thereafter be entitled to vote or exercise any other rights as a shareholder except the right to receive payment for your shares as described herein and the right to maintain an appropriate action to obtain relief on the ground that the merger would be or was fraudulent. In the absence of fraud in the transaction, your right under the dissent provisions described herein is the exclusive remedy for the recovery of the value of your shares of FBC common stock or money damages with respect to the merger.

Withdrawal of Demand. If you have made a written demand on First Financial for payment of the fair value of your FBC common stock, you may withdraw such demand at any time before payment for your shares has been made or before a petition has been filed with a court for determination of the fair value of your shares. If you withdraw your demand or are otherwise unsuccessful in asserting your dissenters’ rights, you will be bound by the merger and your status as a shareholder will be restored without prejudice to any corporate proceedings, dividends or distributions which may have occurred during the interim.

Income Tax Consequences. See“Proposal 1: Approval of the Reorganization Agreement—Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 45 for a discussion on how the federal income tax consequences of your action will change if you elect to dissent from the merger.

PROPOSAL 2: ADJOURNMENT OF THE SPECIAL MEETING

The special meeting may be adjourned or postponed to a later date or dates in order to permit further solicitation of proxies. In order to allow proxies that have been received at the time of the meeting to be voted for an adjournment, if necessary, the voting representatives and board of directors of FBC are submitting the question of adjournment/postponement to the FBC shareholders as a separate matter for their consideration. The voting representatives and the board of directors of FBC recommend that its shareholders vote FOR the adjournment/postponement proposal. If it is necessary to adjourn or postpone the special meeting, no notice of such adjourned or postponed meeting is required to be given to FBC’s shareholders. To adjourn or postpone the special meeting, the affirmative vote of a majority of the shares of FBC common stock present, in person or by proxy, at the meeting is required.

The board of directors of FBC recommends that you vote FOR approval of this proposal.

COMPARISON OF RIGHTS OF SHAREHOLDERS

OF FBC AND FIRST FINANCIAL

The rights of shareholders of FBC under the certificate of formation and bylaws of FBC will differ in some respects from the rights that shareholders of FBC will have as shareholders of First Financial under the certificate of formation and bylaws of First Financial. Copies of First Financial’s certificate of formation and bylaws have been previously filed by First Financial with the SEC. Copies of FBC’s certificate of formation and bylaws are available upon written request from FBC

Certain differences between the provisions contained in the certificate of formation and bylaws of FBC, and the certificate of formation and bylaws of First Financial, as such differences may affect the rights of shareholders, are summarized below. The summary set forth below is not intended to be complete and is qualified by reference to Texas law and, the certificate of formation and bylaws of FBC and the certificate of formation and bylaws of First Financial. If the merger is consummated, holders of FBC common stock (other than dissenting shareholders) will become holders of First Financial common stock, and their rights as holders of First Financial common stock will be governed by the TBOC and First Financial’s certificate of formation and bylaws.

Summary of Material Differences Between Current Rights of

Shareholders of FBC and Rights Those Persons

Will Have as Shareholders of First Financial

		FBC		First Financial
		Directors of FBC are elected at each annual meeting and hold office until their successor is elected and qualified.		If the number of director nominees exceeds the number of directors to be elected, the directors shall be elected by a plurality of the voting power of the shares entitled to vote who are present, in person or by proxy, at any such meeting and entitled to vote on the election of directors.   A majority of the votes cast means that the number of shares voted “for” a proposal, including the election of directors, must exceed the number of shares voted “against,” or “withheld” for, that proposal, and an abstention shall not constitute a vote cast. If, for any cause, the entire Board of Directors shall not have been elected at an annual meeting, any vacancies may be filled by an election as soon thereafter as convenient at a special meeting of the shareholders called for that purpose in the manner provided in the bylaws.
Removal of Directors and Board Vacancies:		FBC’s bylaws provide that at any meeting of FBC’s shareholders, any director may be removed, with or without cause, by a vote of the holders of a majority of the shares then entitled to vote at any election of directors.   Any vacancies existing in the board of directors of FBC may be filled by election at an annual or special meeting of the shareholders or by the affirmative vote of a majority of the remaining directors though less than a quorum of the board of directors, except that any vacancy resulting from the removal of a director by the shareholders may only be filled by the shareholders entitled to vote at an annual meeting or a special meeting called for such purpose. A		First Financial’s bylaws provide that at any meeting of First Financial’s shareholders, any director or the entire board of directors may be removed, with or without cause, by a vote of the holders of a majority of the shares then entitled to vote at any election of directors.   Any vacancies existing in the board of directors of First Financial may be filled by election at an annual or special meeting of the shareholders or by the affirmative vote of a majority of the remaining directors though less than a quorum of the board of directors. A director elected to fill a vacancy will be elected for the unexpired term of his predecessor in office.

		FBC		First Financial
		director elected to fill a vacancy will be elected for the unexpired term of his predecessor in office.   A directorship to be filled by reason of an increase in the number of directors either may be filled by the board of directors for a term of office continuing only until the next election of one or more directors by the shareholders or may be filled by election at an annual meeting or at a special meeting of the shareholders entitled to vote called for that purpose; provided that the board of directors may not fill more than two such directorships during the period between any two successive annual meetings of shareholders		A directorship to be filled by reason of an increase in the number of directors either may be filled by the board of directors for a term of office continuing only until the next election of one or more directors by the shareholders or may be filled by election at an annual meeting or at a special meeting of the shareholders entitled to vote called for that purpose; provided that the board of directors may not fill more than two such directorships during the period between any two successive annual meetings of shareholders.
Vote Required for Certain Shareholder Actions:		FBC’s bylaws provide that the vote of the holders of a majority of the shares entitled to vote and thus represented at a meeting at which a quorum is present is required for any act at a shareholders’ meeting, unless the vote of a greater number is required by law or the certificate of formation.   FBC’s bylaws also provide that each outstanding share of FBC common stock is entitled to one vote on each matter submitted to a vote of shareholders, except to the extent that the voting rights of the shares of any class are limited or denied by the certificate of formation or the TBOC.		First Financial’s bylaws provide that if a quorum exists, action on any matter, including the election of directors, by a voting group shall be approved by the affirmative vote of a majority of the votes cast, unless the certificate of formation, bylaws or applicable law require a greater number of affirmative votes. The bylaws also provide that a majority of the votes cast means that the number of shares voted “for” a proposal, including the election of directors, must exceed the number of shares voted “against,” or “withheld” for, that proposal, and an abstention shall not constitute a vote cast.
Amendment of Certificate of Formation:		FBC’s certificate of formation may be amended in accordance with the TBOC. Under the TBOC, amendments to a corporation’s certificate of formation generally must be approved by the affirmative vote of the holders of two-thirds of the outstanding shares entitled to vote on the amendment.		First Financial’s certificate of formation may be amended in accordance with the TBOC. Under the TBOC, amendments to a corporation’s certificate of formation generally must be approved by the affirmative vote of the holders of two-thirds of the outstanding shares entitled to vote on the amendment.

		FBC		First Financial
Amendment of Bylaws:		FBC’s bylaws provide that the bylaws may be altered, amended or repealed and new bylaws may be adopted by the affirmative vote of a majority of the board of directors, subject to repeal or change by the affirmative vote of a majority of the shareholders.		First Financial’s bylaws provide that the bylaws may be altered, amended or repealed and new bylaws may be adopted by the affirmative vote of a majority of the board of directors, subject to repeal or change by the affirmative vote of a majority of the shareholders.
Shareholder Actions Without a Meeting:		FBC’s certificate of formation provides that any action required by the TBOC to be taken at a meeting of shareholders, or any action which may be taken at any meeting of shareholders, may be taken without a meeting, without prior notice and without a vote, if a consent setting forth the action so taken is signed by the holders of shares representing not less than the minimum number of votes necessary to take such action at a meeting at which the holders of all shares entitled to vote on the action were present and voted.		First Financial’s certificate of formation does not provide for less than unanimous consent when shareholder action is taken without a meeting, and therefore, no action may be taken by written consent unless all shareholders agree.
Special Meetings of Shareholders:		FBC’s bylaws provide that special meetings of FBC’s shareholders may be called by the chairman of the board, the board of directors or the holders not less than 10% of the issued and outstanding shares entitled to vote at such meeting.		First Financial’s bylaws provide that special meetings of the shareholders may be called only by the chairman of the board joined by at least three members of the board of directors, or a majority of the board of directors, and shall be called by the chairman of the board or secretary at the request in writing of shareholders owning not less than 20% of the issued and outstanding shares of First Financial entitled to vote at such meeting.
Nomination of Directors:		Neither FBC’s certificate of formation nor its bylaws contain express provisions regarding the nomination of directors. However, FBC’s bylaws provide that all proposals of shareholders intended to be presented at the annual meeting of shareholders must be received by FBC at its principal offices no later than 90		Nominations for election to the First Financial board of directors may be made by the board of directors or by any shareholder entitled to vote in the election of directors, provided the shareholder gives timely written notice of such intention. To be timely, notice given in the context of an annual meeting of shareholders must be

		FBC		First Financial
		days prior to the date of the annual shareholders’ meeting of each year, in order to be considered for inclusion in the proxy statement and form of proxy for such annual meeting.		received by First Financial not less than 120 days nor more than 150 days in advance of the first anniversary of the preceding year’s annual meeting.
Shareholder Proposal of Business:		FBC’s bylaws provide that all proposals of shareholders intended to be presented at the annual meeting of shareholders must be received by FBC at its principal offices no later than 90 days prior to the date of the annual shareholders’ meeting of each year, in order to be considered for inclusion in the proxy statement and form of proxy for such annual meeting.		Proposals for business to be brought before an annual shareholder meeting may be made by the board of directors or by any shareholder entitled to vote in such meeting. If a proposal is made by a shareholder, the shareholder must give timely written notice. To be timely, notice must be received by First Financial not less than 90 nor more than 120 days in advance of the first anniversary of the preceding year’s annual meeting.
Indemnification; Limitation of Director Liability:		FBC’s certificate of formation provides for mandatory indemnification to the fullest extent allowed by Texas law for all former or present directors or officers and all persons who are or were serving at the request of FBC as a director, officer, partner, manager or similar functionary of another entity.   FBC’s certificate of formation provides that a director shall not be liable to FBC’s or its shareholders for monetary damages for an act or omission in his or her capacity as a director, except for liability for:   •    breach of the duty of loyalty to FBC or its shareholders;   •    an act or omission not in good faith or that involves intentional misconduct or a knowing violation of the law;		First Financial’s certificate of formation and bylaws provide for mandatory indemnification to the fullest extent allowed by Texas law for all former or present directors or officers and all persons who were serving at the request of First Financial as a director, officer, or agent of another entity.   First Financial’s certificate of formation provides that a director shall not be liable to First Financial’s or its shareholders for monetary damages for an act or omission in his or her capacity as a director, except for liability for:   •    breach of the duty of loyalty to First Financial or its shareholders;   •    an act or omission not in good faith or that involves intentional misconduct or a knowing violation of the law;

		FBC		First Financial
		•    a transaction from which the director received an improper benefit, whether or not the benefit resulted from an action taken within the scope of the director’s office; or   •    an act or omission for which the liability of the director is expressly provided by statute.   FBC’s certificate of formation and bylaws provide that the corporation shall have the power to purchase and maintain insurance on behalf of the directors against any liability incurred by directors in such a capacity or arising out of such person’s status.		•    a transaction from which the director received an improper benefit, whether or not the benefit resulted from an action taken within the scope of the director’s office;   •    an act or omission for which the liability of the director is expressly provided by statute; or   •    an act related to an unlawful stock repurchase or payment of a dividend.   First Financial’s certificate of formation and bylaws provide that the corporation shall have the power to purchase and maintain insurance on behalf of the directors against any liability incurred by directors in such a capacity or arising out of such person’s status.

TEXAS ANTI-TAKEOVER STATUTES

First Financial is subject to the affiliated business combinations provisions of Chapter 21, Subchapter M of the TBOC (Sections 21.601 through 21.610), which provide that a Texas corporation may not engage in certain business combinations, including mergers, consolidations and asset sales, with a person, or an affiliate or associate of such person, who is an “Affiliated Shareholder” (generally defined as the holder of 20% or more of the corporation’s voting shares) for a period of three years from the date such person became an Affiliated Shareholder unless: (1) the business combination or purchase or acquisition of shares made by the Affiliated Shareholder was approved by the board of directors of the corporation before the Affiliated Shareholder became an Affiliated Shareholder or (2) the business combination was approved by the affirmative vote of the holders of at least two-thirds of the outstanding voting shares of the corporation not beneficially owned by the Affiliated Shareholder, at a meeting of shareholders called for that purpose (and not by written consent), not less than six months after the Affiliated Shareholder became an Affiliated Shareholder.

The affiliated business combinations provisions of the TBOC are not applicable to:

Neither First Financial’s certificate of formation nor its bylaws contain any provision expressly providing that First Financial will not be subject to the affiliated business combinations provisions of the TBOC. The affiliated business combinations provisions of the TBOC may have the effect of inhibiting a non-negotiated merger or other business combination involving First Financial, even if such event(s) would be beneficial to the shareholders of First Financial.

BUSINESS OF FBC BANCSHARES, INC.

General

FBC was incorporated as a Texas corporation in April 2013 to serve as a bank holding company for First Bank. FBC does not, as an entity, engage in separate business activities of a material nature apart from the activities it performs for First Bank. Its primary activities are to provide assistance in the management and coordination of First Bank’s financial resources. FBC has no significant assets other than all of the outstanding common stock of First Bank. FBC derives its revenues primarily from the operations of First Bank in the form of dividends received from First Bank.

First Bank was chartered as national banking association in May 1985 as First Bank of Conroe, National Association and changed its name to First Bank, National Association in May 2012. Since its inception, First Bank has generally grown organically without any significant acquisitions.

As a bank holding company, FBC is subject to supervision and regulation by the Federal Reserve in accordance with the requirements set forth in the BHC Act and by the rules and regulations issued by the Federal Reserve.

As of March 31, 2015, FBC had, on a consolidated basis, total assets of $382.8 million, total deposits of $342.1 million, total loans (net of unearned discount and allowance for loan losses) of $260.6 million and total shareholders’ equity of $16.4 million. FBC does not file reports with the SEC. FBC does, however, voluntarily provide annual reports, including audited financial statements, to its shareholders in connection with its annual meeting.

Products and Services

First Bank is a traditional commercial bank offering a wide variety of services to satisfy the needs of the consumer and commercial customers in its primary market areas. First Bank offers most types of loans for any legitimate purpose, including loans to small- and medium-sized businesses for the purpose of purchasing equipment, inventory, facilities or for working capital. Consumer loans offered include loans for the purpose of purchasing automobiles, recreational vehicles, personal residences and household goods, and for home improvements needs. Further, First Bank offers mortgage loans with either fixed or variable interest rates to borrowers to purchase, improve and refinance one-to-four family properties. First Bank also provides business and personal depository products and services, including checking and savings accounts, certificates of deposit, money market accounts, debit cards, online banking, direct deposit services, business accounts and cash management services. Travelers checks, money orders and wire transfer services are also available. First Bank’s business is not seasonal in any material respect.

First Bank funds its lending activities primarily from the core deposit base. First Bank obtains deposits from the local market with no material portion (in excess of 10% of total deposits) dependent upon any one person or entity.

Market Area

First Bank currently has eight banking locations, with six locations in Montgomery County, Texas, of which three are located in Conroe and the other three in Magnolia, Montgomery and Willis. First Bank’s two other offices are located in The Woodlands, Harris County, and Huntsville, Walker County, Texas. First Bank’s business is not dependent on one or a few major customers.

Competition

The table below lists First Bank’s deposit market share for certain significant market areas (including Metropolitan Statistical Areas, or MSAs) in which First Bank provides services.

Each activity in which FBC is engaged involves competition with other banks, as well as with nonbanking financial institutions and nonfinancial enterprises. In addition to competing with other commercial banks within and outside its primary service area, FBC competes with other financial institutions engaged in the business of making loans or accepting deposits, such as savings and loan associations, credit unions, industrial loan associations, insurance companies, small loan companies, financial companies, mortgage companies, real estate investment trusts, certain governmental agencies, credit card organizations and other enterprises. FBC also competes with suppliers of equipment in furnishing equipment financing. Banks and other financial institutions with which FBC competes may have capital resources and legal loan limits substantially higher than those maintained by FBC.

Employees

As of March 31, 2015, FBC had 99 full-time equivalent employees, none of whom is covered by a collective bargaining agreement.

Legal Proceedings

There are no threatened or pending legal proceedings against FBC which, if determined adversely, would, in the opinion of management, have a material adverse effect on the business of FBC’s financial condition, results of operations or cash flows.

BENEFICIAL OWNERSHIP OF FBC COMMON STOCK BY

MANAGEMENT AND PRINCIPAL SHAREHOLDERS OF FBC

The following table sets forth certain information regarding the beneficial ownership of FBC common stock as of the record date by: (1) each person who is known by FBC to beneficially own 5% or more of FBC’s common stock; (2) each director of FBC; (3) the principal executive officer, the principal financial officer and the three other most highly compensated executive officers of FBC, or FBC’s named executive officers; and (4) all directors and executive officers of FBC as a group. Unless otherwise indicated, based on information furnished by such shareholders, management of FBC believes that each person has sole voting and dispositive power over the shares indicated as owned by such person. The address for each of the listed beneficial owners is c/o FBC Bancshares, Inc., 1800 West White Oak Terrace, Conroe, Texas 77304.

COMPARATIVE MARKET PRICES AND DIVIDEND DATA

First Financial

First Financial common stock is listed on the NASDAQ Global Select Market under the symbol “FFIN.” Quotations of the sales volume and the closing sales prices of the common stock of First Financial are listed daily in the NASDAQ’s listings.

The following table sets forth, for the periods indicated, the high and low intra-day sales prices for the First Financial common stock as reported by the NASDAQ Global Select Market and the cash dividends declared per share (adjusted for stock dividends and splits):

FBC shareholders are advised to obtain the current stock quotation for First Financial common stock. The market price of First Financial common stock will fluctuate from the date of this proxy statement/prospectus to the date of completion of the merger. Because the number of shares of First Financial common stock to be issued in the merger and the aggregate merger consideration that FBC shareholders will receive will fluctuate based on the market price of the First Financial common stock, FBC shareholders will not know the exact amount of the value of the consideration that FBC shareholders will receive in connection with the merger when FBC shareholders vote on the reorganization agreement and merger.

After the merger, First Financial currently expects to pay (when, as and if declared by First Financial’s board of directors out of funds legally available for that purpose) regular quarterly cash dividends. While First Financial currently pays dividends on its common stock, there is no assurance that it will continue to pay dividends in the future. Future dividends on First Financial common stock will depend upon its earnings and financial condition, liquidity and capital requirements, the general economic and regulatory climate, its ability to service any equity or debt obligations senior to the common stock and other factors deemed relevant by the board of directors of First Financial.

As a holding company, First Financial is ultimately dependent upon its subsidiaries to provide funding for its operating expenses, debt service and dividends. Various banking laws applicable to First Financial Bank limit the payment of dividends and other distributions by First Financial Bank to First Financial, and may therefore limit First Financial’s ability to pay dividends on its common stock. Regulatory authorities could impose administratively stricter limitations on the ability of First Financial Bank to pay dividends to First Financial if such limits were deemed appropriate to preserve certain capital adequacy requirements.

FBC

There is no established public trading market for the common stock of FBC, and no market for FBC’s common stock is expected to develop if the merger does not occur. No registered broker/dealer makes a market in FBC’s common stock, and FBC’s common stock is not listed or quoted on any stock exchange or automated quotation system. FBC acts as the transfer agent and registrar for its own shares. As of the record date, there were approximately 49 holders of FBC’s common stock.

FBC is not aware of any trades in its common stock since its formation in 2013. The most recent trade of First Bank’s common stock, prior to the formation of FBC, occurred on December 20, 2012, when 600 shares were traded at a price of $52.00 per share. There were other limited transfers of First Bank’s common stock prior to that time, including transfers between related parties (as gifts or to trusts or estates). Because of limited trading, the price described above may not be representative of the actual or fair value of FBC’s common stock. FBC is not obligated to register its common stock or, upon any registration, to create a market for its stock.

FBC’s shareholders are entitled to receive dividends out of legally available funds as and when declared by FBC’s board of directors, in its sole discretion. As a Texas corporation, FBC is subject to certain restrictions on dividends under the TBOC. Generally, a Texas corporation may pay dividends to its shareholders out of its surplus (the excess of its assets over its liabilities and stated capital) unless the corporation is insolvent or the payment of the dividend would render the corporation insolvent.

FBC has not paid dividends on its common stock since its inception in 2013. However, in connection with the revocation of First Bank’s subchapter S election and the formation of FBC as a bank holding company for First Bank in 2013, FBC distributed to its shareholders a portion of the accumulated adjustment account in the amount of approximately $13.1 million in aggregate principal amount of subordinated promissory notes due June 30, 2028, which will be paid in full by First Financial shortly after closing the merger. FBC has used dividends received from First Bank to service the outstanding subordinated promissory notes.

FBC does not engage in separate business activities of a material nature. As a result, FBC’s ability to pay dividends depends upon the dividends received from First Bank. As a national banking association, First Bank’s ability to pay dividends is restricted by certain laws and regulations. Under 12 U.S.C. § 56, a national bank cannot pay dividends on its stock from its capital stock and surplus accounts. All dividends on its stock must be paid out of net profits after making deductions for expenses, including losses and provisions for loan losses. As of March 31, 2015, First Bank had retained earnings of $11.4 million. The payment of dividends out of net profits is further restricted by 12 U.S.C. § 60(a), which limits a national bank when declaring dividends on its shares of stock until its capital surplus equals the amount of capital stock or if the surplus fund does not equal the amount of capital stock, by requiring a portion of the bank’s net income to be transferred to the surplus account each time dividends are declared. For this purpose, “net profits” means the remainder of all earnings from current operations plus actual recoveries on loans and investments and other assets after deducting from the total thereof all current operating expenses, actual losses and all federal and state taxes. In addition, 12 U.S.C. § 60(b) places a recent earnings limitation on the payment of dividends by a national bank by requiring prior approval by the OCC of a dividend if the total of all dividends declared by a national bank in any year exceeds the total of its net income of that year combined with retained net income of the two preceding years, less any required transfer to surplus. The OCC further restricts the ability of national banks to pay any dividends by preventing national banks from including provisions for loan losses in “net profits” and thus reducing the funds available for payment of dividends.

DESCRIPTION OF FIRST FINANCIAL CAPITAL STOCK

General

First Financial has authorized 120,000,000 shares of First Financial common stock, par value $0.01 per share, [            ]64,156,302 shares of which are outstanding as of [                    ],June 17, 2015. The following summary is qualified in its entirety by reference to the certificate of formation and bylaws of First Financial.

First Financial common stock

The holders of First Financial common stock are entitled to one vote for each share of First Financial common stock owned. Holders of First Financial common stock may not cumulate their votes for the election of directors. Holders of First Financial common stock do not have preemptive rights to acquire any additional, unissued or treasury shares of First Financial. First Financial common stock is not convertible into any other security of First Financial and does not carry a right to subscribe to or acquire shares of First Financial.

Holders of First Financial common stock will be entitled to receive dividends out of funds legally available therefor, if and when properly declared by the First Financial board. On liquidation of First Financial, the holders of First Financial common stock are entitled to share pro rata in any distribution of the assets of First Financial after all other indebtedness of First Financial has been retired.

EXPERTS

The consolidated financial statements of First Financial Bankshares, Inc. at December 31, 2014 and 2013, and for each of the three years in the period ended December 31, 2014, incorporated by reference in the Proxy Statement of First Financial Bankshares, Inc. which is referred to and made a part of this Prospectus and Registration Statement, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report, and are included in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

LEGAL MATTERS

The validity of the shares of First Financial common stock to be issued by First Financial in connection with the merger will be passed upon by Norton Rose Fulbright US LLP, Dallas, Texas. Certain legal matters with respect to the merger will be passed upon for FBC by Fenimore, Kay, Harrison & Ford, LLP, Austin, Texas.

OTHER MATTERS

As of the date of this proxy statement/prospectus, the board of directors of FBC knows of no matters that will be presented for consideration at the special meeting of shareholders other than as described in this proxy statement/prospectus. However, if any other matters are properly brought before the special meeting or any adjournment or postponement thereof, it is intended that the proxies will act in accordance with their best judgment unless otherwise indicated in the appropriate box on the proxy.

WHERE YOU CAN FIND MORE INFORMATION

First Financial files reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934. You may read and copy this information at the SEC’s Public Reference Room, 100 F Street, N.E., Washington, D.C. 20549.

You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy and information statements and other information about issuers, like First Financial, who file electronically with the SEC. The address of that site is http://www.sec.gov.

The SEC allows First Financial to “incorporate by reference” information in this proxy statement/prospectus. This means that First Financial can disclose important business and financial information to you by referring you to another document filed separately with the SEC. The information that First Financial incorporates by reference is considered to be part of this proxy statement/prospectus, and later information that First Financial files with the SEC will automatically update and supersede the information First Financial included in this proxy statement/prospectus. This document incorporates by reference the documents that are listed below that First Financial has previously filed with the SEC, except to the extent that any information contained in such filings is deemed “furnished” in connection with SEC rules.

First Financial SEC Filings (File Number: 000-07674)

First Financial also incorporates by reference any future filings it makes with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this proxy statement/prospectus and before the meeting. Any statement contained in this proxy statement/prospectus or in a document incorporated or deemed to be incorporated by reference in this proxy statement/prospectus is deemed to be modified or superseded to the extent that a statement contained herein or in any subsequently filed document that also is, or is deemed to be, incorporated by reference herein modified or superseded such statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this proxy statement/prospectus.

Documents incorporated by reference are available from First Financial without charge (except for exhibits to the documents unless the exhibits are specifically incorporated in the document by reference). You may obtain documents incorporated by reference in this document by requesting them in writing or by telephone from First Financial at the following address:

First Financial Bankshares, Inc.

400 Pine Street

Abilene, Texas 79601

Attention: J. Bruce Hildebrand,

Executive Vice President and

Chief Financial Officer

Telephone: (325) 625-7155

To obtain timely delivery, you must make a written or oral request for a copy of such information by [                    ],July 16, 2015.

First Financial has filed a registration statement on Form S-4 under the Securities Act with the SEC with respect to the First Financial common stock to be issued to shareholders of FBC in the merger. This proxy statement/prospectus constitutes the prospectus of First Financial filed as part of the registration statement. This proxy statement/prospectus does not contain all of the information set forth in the registration statement because certain parts of the registration statement are omitted in accordance with the rules and regulations of the SEC. The registration statement and its exhibits are available for inspection and copying as set forth above.

You should rely only on the information contained in this proxy statement/prospectus. Neither First Financial nor FBC has authorized anyone to provide you with different information. Therefore, if anyone gives you different or additional information, you should not rely on it. The information contained in this proxy statement/prospectus is correct as of its date. It may not continue to be correct after this date. FBC has supplied all of the information about FBC and First Bank contained in this proxy statement/prospectus and First Financial has supplied all of the information contained in this proxy statement/prospectus about First Financial and its subsidiaries. Each of us is relying on the correctness of the information supplied by the other.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to purchase, the securities offered by this proxy statement/prospectus, or the solicitation of a proxy, in any jurisdiction to or from any person to whom or from it is unlawful to make such offer, solicitation of an offer or proxy solicitation in such jurisdiction.

Appendix A

AGREEMENT AND PLAN OF REORGANIZATION

BY AND BETWEEN

FIRST FINANCIAL BANKSHARES, INC.

AND

FBC BANCSHARES, INC.

Dated as of April 1, 2015

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