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 “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 whetherhow to vote for approval ofon the asset sale and the merger agreement. If any of the risks describedproposals presented in this proxy statement/prospectus occur, First Financial’s financial condition, resultsprospectus. See “Where You Can Find More Information” beginning on page 68.

The merger may not be completed.

Completion of operations and cash flows could be materially and adversely affected. If this werethe merger is subject to happen, the value ofregulatory approval. First Financial common stock could decline significantly,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 could losethat all of the conditions precedent in the reorganization agreement will be satisfied or part of your investment.that the merger will be completed.

Risks Associated With the Asset Sale

Because theThe number of shares of First Financial common stock to be received by OSB Financialas merger consideration will fluctuate, and shareholders of FBC may receive more or less value, depending upon increases and decreases in the asset sale is fixed and will not be adjusted if there is any change in themarket price of First FinancialFinancial’s common stock and the cash consideration may be decreased, you will not know the valueconsolidated shareholders’ equity of theFBC prior to closing.

The aggregate number of shares of First Financial common stock or amount of cash OSB Financial will receiveissued to FBC shareholders in exchange for the common stockeach share of Orange Savings Bank, SSB when you vote on the asset sale.

Upon completion of the asset sale, all shares of Orange Savings Bank, SSB common stockFBC will be exchanged for 420,000 shares of First Financial common stock and $39.2 million in cash, subject to adjustment. The number of First Financial shares is fixed and will not be adjusted as a result of any change in the market price of First Financial common stock. In addition, neither First Financial nor OSB Financial may terminate the merger agreement solely because offluctuate based upon changes in the market price of First Financial’s common stock. Therefore, ifstock and the priceconsolidated shareholders’ equity of First Financial common stock declinesFBC prior to the completionclosing of the asset sale,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 tomay be received by OSB Financial and subsequently distributed to shareholdersthe result of OSB Financial will decline. The price of First Financial common stock is by nature subject to the general price fluctuations in the market for publicly-traded equity securities, has experienced volatility and may decline for a number of reasons,various factors, many of which are outbeyond the control of First Financial and FBC, including:

The merger may not be completed until a significant period of time has passed after the market prices of its common stock onFBC’s shareholders’ meeting. At the datetime of the OSB Financial specialshareholder meeting, the date of the completion of the asset sale or at any time after the completion of the asset sale. Shareholders of OSB Financial are encouraged to obtain current market price quotations for First Financial common stock before voting their shares at the special meeting.

If Orange Savings Bank, SSB’s equity capital as of the Calculation Date is less than $43.2 million, the cash portion of the consideration will be reduced by an amount equal to the difference between Orange Savings Bank, SSB’s equity capital on the Calculation Date and $43.2 million, as calculated in the manner set forth in the merger agreement. Pursuant to the terms of the merger agreement, equity capital of Orange Savings Bank, SSB means the sum of the capital stock, capital surplus and retained earnings of Orange Savings Bank, SSB, excluding unrealized securities gains or losses, on a consolidated basis, as determined pursuant to generally accepted accounting principles (“GAAP”), with such amounts to be calculated in accordance with the methodology used in the Orange Savings Bank, SSB Report of Condition and Income to calculate the total equity capital (Call Report Schedule RC—Balance Sheet, item 27.a). For purposes of calculating equity capital, Orange Savings Bank, SSB must include adjustments made for certain items related to the asset sale and the merger, including certain merger related costs, as more fully described herein and in the merger agreement.

After completion of the asset sale, OSB Financial intends to distribute the consideration, after repayment of its obligations and expenses, including repayment of all of its outstanding trust preferred promissory notes and 2009 Senior Secured Notes Due December 31, 2020, to the holders of the OSB common stock, other than dissentingFBC shareholders subject to OSB Financial’s obligation under the merger agreement to maintain ownership of cash or other assets (other than shares of First Financial common stock) with a net fair market value of at least $1,000,000 in excess of any liabilities of OSB Financial until December 30, 2013.

Thus, the cash portion of the consideration may be reduced by amounts used by OSB Financial (i) to pay its obligations and expenses, including repayment of its outstanding trust preferred promissory notes and 2009 Senior Secured Notes Due December 31, 2020, (ii) to maintain ownership of cash or other assets (other than shares of First Financial common stock) with a net fair market value of at least $1,000,000 in excess of any liabilities of OSB Financial until December 30, 2013, and (iii) to pay costs and expenses related to a potential liquidation of OSB Financial after December 30, 2013. Accordingly, you will not know the exact amountnumber of shares or the value of the cash portion of the considerationFirst Financial common stock that OSB Financial will receivebe issued in connection with the asset sale when you vote on the asset sale and the merger agreement. Moreover, for the reasons given above, you will not know the exact amount of the cash portion of the consideration OSB Financial will distribute to its shareholders or OSB Financial’s timing for paying any such distribution when you vote on the asset sale and the merger agreement.merger.

The market price of First Financial common stock after the asset salemerger may be affected by factors different from those affecting OSB FinancialFBC common stock or First Financial common stock currently.

The businesses of First Financial and OSB FinancialFBC 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 asset salemerger may

be affected by factors different from those currently affecting the independent results of operations of each of First Financial and OSB FinancialFBC. 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 or waive approvalFirst Financial’s acquisition of the asset sale and the mergerFBC and the OCC must approve the merger.merger of First Bank with and into First Financial Bank. On March 8, 2013,April 10, 2015, First Financial filed an application with the Federal Reserve waivedto obtain approval of the approval requirementsmerger under the BHC Act subjectand 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 merger byFederal Reserve and the OCC.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

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 whether thissafety and othersoundness. Further, regulatory approvals will be received,approval is not an opinion that the timingproposed merger is favorable to the shareholders of those approvalseither party to the merger from a financial point of view or whether any conditions will be imposed.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.

OSB FinancialFBC will be subject to business uncertainties while the asset salemerger is pending.

Uncertainty about the effect of the asset salemerger on employees and customers of FBC may have an adverse effect on Orange SavingsFBC and its wholly-owned subsidiary, First Bank, SSB and consequently on First Financial following completion of the asset sale.merger. These uncertainties may impair Orange Savings Bank, SSB’sFBC’s ability to attract, retain and motivate key personnel until the asset salemerger is completed, and could cause customers and others that deal with Orange Savings Bank, SSBFBC to seek to change existing business relationships with Orange Savings Bank, SSB. Although Orange Savings Bank, SSB has entered into retention bonus agreements with its officers (as discussed herein), retentionFBC. Retention of certain employees of FBC and First Bank may be challenging while the asset salemerger 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 asset salemerger could be harmed. See the section entitled “Proposal 1: Approval of Asset Sale and Mergerthe Reorganization Agreement—Conduct of Business Pending Effective Time” beginning on page 4135 of this proxy statement/prospectus for a description of the restrictive covenants to which OSB Financial and Orange Savings Bank, SSB areFBC is subject.

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

First Financial Bank N.A. and Orange SavingsFirst Bank SSB have historically operated and, until the asset salebank 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 asset sale.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 asset sale and 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 asset sale and the merger may not be realized.

Some of the directors and officers of OSB Financial and Orange Savings Bank, SSBFBC may have interests and arrangements that may have influenced their decisions to support or recommend that you approve the asset sale.reorganization agreement and the transactions contemplated therein.

The interests of some of the directors and officers of OSB Financial and Orange Savings Bank, SSBFBC may be different from those of OSB FinancialFBC shareholders, and such directors and officers may be participants in arrangements that are different from, or in addition to, those of OSB FinancialFBC 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 OSB FinancialFBC in the Asset SaleMerger”” beginning on page 49.43.

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

Although First Financial estimates that it will realize cost savings from the asset sale and the merger when fully phased in,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 N.A. and Orange SavingsFirst Bank SSB 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.

OSB FinancialFBC shareholders will have a reduced ownership and voting interest after the asset salemerger and will exercise less influence over management.

The asset salemerger will transfer control of Orange Savings Bank, SSBFBC to First Financial and to the shareholders of First Financial. When the asset salemerger is completed, each OSB FinancialFBC shareholder (other than dissenting shareholders) will continue to own shares of OSB Financial and, subsequent to OSB Financial’s distribution of First Financial stock, will also become shareholdersa shareholder of First Financial with a percentage ownership of First Financial much smaller than such shareholder’s percentage ownership of OSB FinancialFBC. Because of this, OSB FinancialFBC shareholders will have less influence on the management and policies of First Financial, and thus First Financial Bank, N.A., than they now have on the management and policies of OSB Financial and Orange Savings Bank, SSB.

Risks Associated With First Financial’s Business

First Financial’s business faces unpredictable economic conditions, which could have an adverse effect on its financial condition, results of operations and liquidity.

General economic conditions impact the banking industry. The credit quality of First Financial’s loan portfolio necessarily reflects, among other things, the general economic conditions in the areas in which First Financial conducts business. First Financial’s continued financial success depends somewhat on factors beyond its control, including:

Any substantial deterioration in any of the foregoing conditions could have a material adverse effect on First Financial’s financial condition, results of operations and liquidity, which would likely adversely affect the market price of First Financial’s common stock.

First Financial must effectively manage its credit risk.

As a lender, First Financial is exposed to the risk that its loan customers may not repay their loans according to the terms of these loans and the collateral securing the payment of these loans may be insufficient to fully compensate First Financial for the outstanding balance of the loan plus the costs to dispose of the collateral. First Financial may experience significant loan losses, which could have a material adverse effect on its operating results and financial condition. Management makes various assumptions and judgments about the collectibility of First Financial’s loan portfolio, including the diversification by industry of First Financial’s commercial loan portfolio, the amount of nonperforming loans and related collateral, the volume, growth and composition of First Financial’s loan portfolio, the effects on the loan portfolio of current economic indicators and their probable impact on borrowers and the evaluation of First Financial’s loan portfolio through its internal loan review process and other relevant factors.

First Financial maintains an allowance for credit losses, which is an allowance established through a provision for loan losses charged to expense that represents management’s best estimate of probable losses inherent in our loan portfolio. Additional credit losses will likely occur in the future and may occur at a rate greater than we have experienced to date. In determining the amount of the allowance, First Financial relies on an analysis of its loan portfolio, its experience and its evaluation of general economic conditions. If First Financial’s assumptions prove to be incorrect, its current allowance may not be sufficient and adjustments may be necessary to allow for different economic conditions or adverse developments in its loan portfolio. Material additions to the allowance could materially decrease First Financial’s net income.

In addition, banking regulators periodically review First Financial’s allowance for credit losses and may require First Financial to increase its provision for credit losses or recognize further charge-offs, based on judgments different than those of First Financial’s management. Any increase in First Financial’s allowance for credit losses or charge-offs as required by these regulatory agencies could have a material negative effect on First Financial’s operating results, financial condition and liquidity.

First Financial’s business is concentrated in Texas and a downturn in the economy of Texas may adversely affect First Financial’s business.

First Financial’s network of bank regions is concentrated in Texas, primarily in the Western and North Central regions of the state. Most of First Financial’s customers and revenue are derived from this area. The economy of this region is focused on agriculture (including farming and ranching), commercial and industrial, medical, education, wind energy, manufacturing, service, oil and gas production, and real estate. Because First Financial generally does not derive revenue or customers from other parts of the state or nation, First Financial’s business and operations are dependent on economic conditions in this part of Texas. Any significant decline in one or more segments of the local economy could adversely affect First Financial’s business, revenue, operations and properties.FBC.

Changes in economic conditions could cause an increase in delinquencies and non-performing assets, including loan charge-offs, which could depress First Financial’s net income and growth.

First Financial’s loan portfolios include many real estate secured loans, demand for which may decrease during economic downturns as a result of, among other things, an increase in unemployment, a decrease in real estate values and, a slowdown in housing. If First Financial continues to see negative economic conditions in the United States as a whole or in the portions of Texas that First Financial serves, First Financial could experience higher delinquencies and loan charge-offs, which would reduce First Financial’s net income and adversely affect its financial condition. Furthermore, to the extent that real estate collateral is obtained through foreclosure, the costs of holding and marketing the real estate collateral, as well as the ultimate values obtained from disposition, could reduce First Financial’s earnings and adversely affect its financial condition.

The value of real estate collateral may fluctuate significantly resulting in an under-collateralized loan portfolio.

The market value of real estate, particularly real estate held for investment, can fluctuate significantly in a short period of time as a result of market conditions in the geographic area in which the real estate is located. If the value of the real estate serving as collateral for First Financial’s loan portfolio were to decline materially, a significant part of First Financial’s loan portfolio could become under-collateralized. If the loans that are collateralized by real estate become troubled during a time when market conditions are declining or have declined, then, in the event of foreclosure, First Financial may not be able to realize the amount of collateral that it anticipated at the time of originating the loan. This could have a material adverse effect on First Financial’s provision for loan losses and its operating results and financial condition.

The repeal of prohibitions on paying of interest on demand deposits could increase First Financial’s interest expense.

Effective in July 2011, all federal prohibitions on financial institutions paying interest on demand deposit accounts were repealed as part of the Dodd-Frank Act. As a result, some financial institutions have commenced and are considering offering interest on demand deposits to compete for customers. First Financial’s interest expense could increase and its net interest margin could decrease if First Financial begins offering interest on demand deposits to maintain current customers or attract new customers, which could have a material adverse effect on First Financial’s financial condition and results of operations.

First Financial does business with other financial institutions that could experience financial difficulty.

First Financial does business through the purchase and sale of federal funds, check clearing and through the purchase and sale of loan participations with other financial institutions. Because these financial institutions have many risks, as does First Financial, First Financial could be adversely affected should one of these financial institutions experience significant financial difficulties or fail to comply with First Financial’s agreements with them.

Recent developments in the mortgage market may affect First Financial’s ability to originate loans and the profitability of loans in its mortgage pipeline.

During the past several years, the real estate housing market throughout the United States has softened resulting in an industry-wide increase in borrowers unable to make their mortgage payments and increased foreclosure rates. Lenders in certain sections of the housing and mortgage markets were forced to close or limit their operations or seek additional capital. In response, financial institutions have tightened their underwriting standards, limiting the availability of sources of credit and liquidity. If the housing/real estate market continues to have problems in the future, there could be a prolonged decrease in the demand for First Financial’s loans in the secondary market, adversely affecting its earnings.

If First Financial is unable to continue to originate residential real estate loans and sell them into the secondary market for a profit, First Financial’s earnings could decrease.

First Financial derives a portion of its noninterest income from the origination of residential real estate loans and the subsequent sale of such loans into the secondary market. If First Financial is unable to continue to originate and sell residential real estate loans at historical or greater levels, its residential real estate loan volume would decrease, which could decrease its earnings. A rising interest rate environment, general economic conditions or other factors beyond its control could adversely affect First Financial’s ability to originate residential real estate loans. First Financial also is experiencing an increase in regulations and compliance requirements related to mortgage loan originations necessitating technology upgrades and other changes. If new regulations continue to increase and First Financial is unable to make technology upgrades, First Financial’s ability to originate mortgage loans will be reduced or eliminated. Additionally, First Financial sells a large portion of its residential real estate loans to third party investors, and rising interest rates could negatively affect its ability to generate suitable profits on the sale of such loans. If interest rates increase after First Financial originates the loans, its ability to market those loans is impaired as the profitability on the loans decreases. These fluctuations can have an adverse effect on the revenue First Financial generates from residential real estate loans and in certain instances, could result in a loss on the sale of the loans.

Further, for the mortgage loans First Financial sells in the secondary market, the mortgage loan sales contracts contain indemnification clauses should the loans default, generally in the first sixty to ninety days, or if documentation is determined not to be in compliance with regulations. While First Financial’s historic losses as a result of these indemnities have been insignificant, First Financial could be required to repurchase the mortgage loans or reimburse the purchaser of its loans for losses incurred. Both of these situations could have an adverse effect on the profitability of First Financial’s mortgage loan activities and negatively impact its net income.

First Financial may need to raise additional capital/liquidity and such funds may not be available when needed.

First Financial may need to raise additional capital/liquidity in the future to provide it with sufficient capital resources and liquidity to meet its commitments and business needs, particularly if its asset quality or earnings were to deteriorate significantly. First Financial’s ability to raise additional capital/liquidity, if needed, will depend on, among other things, conditions in the capital and financial markets at that time, which are outside of First Financial’s control, and its financial performance. Economic conditions and the loss of confidence in financial institutions may increase First Financial’s cost of funding and limit access to certain customary sources of capital/liquidity, including depositors, other financial institution borrowings, repurchase agreements and borrowings from the discount window of the Federal Reserve. Any occurrence that may limit First Financial’s access to the capital/liquidity markets, such as a decline in the confidence of other financial institutions, depositors or counterparties participating in the capital markets, may adversely affect First Financial’s costs and its ability to raise capital/liquidity. An inability to raise additional capital/liquidity on acceptable terms when needed could have a materially adverse effect on First Financial’s financial condition, results of operations and liquidity.

The trust wealth management fees First Financial receives may decrease as a result of poor investment performance, in either relative or absolute terms, which could decrease its revenues and net earnings.

First Financial’s trust company subsidiary derives its revenues primarily from investment management fees based on assets under management. First Financial’s ability to maintain or increase assets under management is subject to a number of factors, including investors’ perception of its past performance, in either relative or absolute terms, market and economic conditions, including changes in oil and gas prices, and competition from investment management companies. Financial markets are affected by many factors, all of which are beyond First Financial’s control, including general economic conditions, including changes in oil and gas prices; securities market conditions; the level and volatility of interest rates and equity prices; competitive conditions; liquidity of global markets; international and regional political conditions; regulatory and legislative

developments; monetary and fiscal policy; investor sentiment; availability and cost of capital; technological changes and events; outcome of legal proceedings; changes in currency values; inflation; credit ratings; and the size, volume and timing of transactions. A decline in the fair value of the assets under management, caused by a decline in general economic conditions, would decrease First Financial’s wealth management fee income.

Investment performance is one of the most important factors in retaining existing clients and competing for new wealth management clients. Poor investment performance could reduce First Financial’s revenues and impair its growth in the following ways:

Even when market conditions are generally favorable, First Financial’s investment performance may be adversely affected by the investment style of its wealth management and investment advisors and the particular investments that they make. To the extent First Financial’s future investment performance is perceived to be poor in either relative or absolute terms, the revenues and profitability of its wealth management business will likely be reduced and its ability to attract new clients will likely be impaired. As such, fluctuations in the equity and debt markets can have a direct impact upon First Financial’s net earnings.

Certain of First Financial’s investment advisory and wealth management contracts are subject to termination on short notice, and termination of a significant number of investment advisory contracts could have a material adverse impact on First Financial’s revenue.

Certain of First Financial’s investment advisory and wealth management clients can terminate, with little or no notice, their relationships with us, reduce their aggregate assets under management, or shift their funds to other types of accounts with different rate structures for any number of reasons, including investment performance, changes in prevailing interest rates, inflation, changes in investment preferences of clients, changes in First Financial’s reputation in the marketplace, change in management or control of clients, loss of key investment management personnel and financial market performance. We cannot be certain that First Financial’s trust company subsidiary will be able to retain all of its clients. If its clients terminate their investment advisory and wealth management contracts, First Financial’s trust company subsidiary, and consequently First Financial, could lose a substantial portion of its revenues.

First Financial is subject to possible claims and litigation pertaining to fiduciary responsibility.

From time to time, customers could make claims and take legal action pertaining to First Financial’s performance of its fiduciary responsibilities. Whether customer claims and legal action related to First Financial’s performance of its fiduciary responsibilities are founded or unfounded, if such claims and legal actions are not resolved in a manner favorable to First Financial, they may result in significant financial liability and/or adversely affect First Financial’s market perception of its products and services as well as impact customer demand for those products and services. Any financial liability or reputation damage could have a material adverse effect on First Financial’s business, which, in turn, could have a material adverse effect on its financial condition and results of operations.

First Financial’s business is subject to significant government regulation.

First Financial operates in a highly regulated environment and is subject to supervision and regulation by a number of governmental regulatory agencies, including the Federal Reserve, the OCC, and the FDIC.

Regulations adopted by these agencies, which are generally intended to provide protection for depositors and customers rather than for the benefit of shareholders, govern a comprehensive range of matters relating to ownership and control of First Financial’s shares, its acquisition of other companies and businesses, permissible activities for First Financial to engage in, maintenance of adequate capital levels and other aspects of First Financial’s operations. The bank regulatory agencies possess broad authority to prevent or remedy unsafe or unsound practices or violations of law.

The Dodd-Frank Act, enacted in July 2010, instituted major changes to the banking and financial institutions regulatory regimes in light of the recent performance of and government intervention in the financial services sector. Other changes to statues, regulations or regulatory policies, including changes in interpretation or implementation of statutes, regulations or policies, could affect First Financial in substantial and unpredictable ways. Such changes could subject First Financial to reduced revenues, additional costs, limit the types of financial services and products First Financial may offer and/or increase the ability of non-banks to offer competing financial services and products, among other things. Failure to comply with laws, regulations or policies could result in sanctions by regulatory agencies, civil money penalties and/or reputation damage, which could have a material adverse effect on First Financial’s business, financial condition and results of operations.

Included in the Dodd-Frank Act are, for example, changes related to interchange fees and overdraft services. While the changes for interchange fees that can be charged for electronic debit transactions by payment card issuers relate only to banks with assets greater than $10 billion, concern exists that the regulations will also impact our First Financial. Beginning in the third quarter of 2010, we were prohibited from charging customers fees for paying overdrafts on automated teller machine and debit card transactions, unless the consumer opts in. First Financial continues to monitor the impact of these new regulations and other developments on First Financial’s service charge revenue.

First Financial’s FDIC insurance assessments could increase substantially resulting in higher operating costs.

First Financial has historically paid the lowest premium rate available due to our sound financial position. In 2009, a special assessment ($1.4 million for First Financial) was paid by First Financial. Should bank failures continue to occur, FDIC premiums could remain high or increase or additional special assessments could be imposed. These increased premiums would have an adverse effect on First Financial’s net income and results of operations.

First Financial competes with many larger financial institutions which have substantially greater financial resources than First Financial.

Competition among financial institutions in Texas is intense. First Financial competes with other bank holding companies, state and national commercial banks, savings and loan associations, consumer financial companies, credit unions, securities brokers, insurance companies, mortgage banking companies, money market mutual funds, asset-based non-bank lenders and other financial institutions. Many of these competitors have substantially greater financial resources, larger lending limits, larger branch networks and less regulatory oversight than First Financial has, and are able to offer a broader range of products and services than First Financial can. Failure to compete effectively for deposit, loan and other banking customers in First Financial’s markets could cause it to lose market share, slow its growth rate and may have an adverse effect on First Financial’s financial condition, results of operations and liquidity.

First Financial is subject to interest rate risk.

First Financial’s profitability is dependent to a large extent on its net interest income, which is the difference between interest income First Financial earns as a result of interest paid to it on loans and investments and interest it pays to third parties such as its depositors and those from whom its borrows funds. Like most financial

institutions, First Financial is highly sensitive to many factors that are beyond its control, including general economic conditions and policies of various governmental and regulatory agencies and, in particular, the Federal Reserve. Changes in monetary policy, including changes in interest rates, could influence not only the interest First Financial receives on loans and securities and the amount of interest it pays on deposits and borrowings, but such changes could also affect (i) First Financial’s ability to originate loans and obtain deposits, (ii) the fair value of First Financial’s financial assets and liabilities, and (iii) the average duration of First Financial’s securities portfolio. If the interest rates paid on deposits and other borrowings increase at a faster rate than the interest rates received on loans and investments, First Financial’s net interest income, and earnings, could be adversely affected. Earnings could also be adversely affected if the interest rates received on loans and investments fall more quickly than the interest rates paid on deposits and other borrowings.

Although First Financial has implemented strategies which it believes reduce the potential effects of adverse changes in interest rates on its results of operations, these strategies may not always be successful. In addition, any substantial and prolonged increase in market interest rates could reduce First Financial’s customers’ desire to borrow money from First Financial or adversely affect their ability to repay their outstanding loans by increasing their credit costs since most of First Financial’s loans have adjustable interest rates that reset periodically. Any of these events could adversely affect First Financial’s results of operations, financial condition and liquidity.

First Financial relies on dividends from its subsidiaries for most of its revenue.

First Financial is a separate and distinct legal entity from its subsidiaries. It receives substantially all of its revenue from dividends paid by its subsidiaries. These dividends are the principal source of funds to pay dividends on First Financial’s common stock and interest and principal on First Financial debt (if First Financial had balances outstanding). Various federal and/or state laws and regulations limit the amount of dividends that First Financial’s bank subsidiaries may pay to First Financial. In the event First Financial’s subsidiaries are unable to pay dividends to First Financial, First Financial may not be able to service debt or pay dividends on First Financial’s common stock. The inability to receive dividends from First Financial’s subsidiaries could have a material adverse effect on First Financial’s business, financial condition, results of operations and liquidity.

To continue First Financial’s growth, First Financial is affected by its ability to identify and acquire other financial institutions.

First Financial intends to continue its current growth strategy. This strategy includes opening new branches and acquiring other banks that serve customers or markets First Financial finds desirable. The market for acquisitions remains highly competitive, and First Financial may be unable to find satisfactory acquisition candidates in the future that fits First Financial’s acquisition and growth strategy. To the extent that First Financial is unable to find suitable acquisition candidates, an important component of First Financial’s growth strategy may be lost. Additionally, First Financial’s completed acquisitions, or any future acquisitions, may not produce the revenue, earnings or synergies that First Financial anticipated.

Use of First Financial’s common stock for future acquisitions or to raise capital may be dilutive to existing stockholders.

When First Financial determines that appropriate strategic opportunities exist, First Financial may acquire other financial institutions and related businesses, subject to applicable regulatory requirements. First Financial may use its common stock for such acquisitions. From time to time, First Financial may also seek to raise capital through selling additional common stock. It is possible that the issuance of additional common stock in such acquisition or capital transactions may be dilutive to the interests of First Financial’s existing shareholders.

First Financial’s operational and financial results are affected by its ability to successfully integrate its acquisitions.

Acquisitions of financial institutions involve operational risks and uncertainties and acquired companies may have unforeseen liabilities, exposure to asset quality problems, key employee and customer retention problems and other problems that could negatively affect First Financial’s organization. First Financial may not be able to successfully integrate the operations, management, products and services of the entities that First Financial acquires nor eliminate redundancies. The integration process may also require significant time and attention from our management that they would otherwise direct at servicing existing business and developing new business. First Financial’s failure to successfully integrate the entities we acquire into First Financial’s existing operations may increase its operating costs significantly and adversely affect its business and earnings.

The value of our goodwill and other intangible assets may decline in the future.

As of December 31, 2012, First Financial had $72.0 million of goodwill and other intangible assets. A significant decline in our financial condition, a significant adverse change in the business climate, slower growth rates or a significant and sustained decline in the price of First Financial’s common stock may necessitate taking charges in the future related to the impairment of First Financial’s goodwill and other intangible assets. If First Financial was to conclude that a future write-down of goodwill and other intangible assets is necessary, First Financial would record the appropriate charge, which could have a material adverse effect on First Financial’s financial condition and results of operations.

First Financial relies heavily on its management team, and the unexpected loss of key management may adversely affect its operations.

First Financial’s success to date has been strongly influenced by our ability to attract and to retain senior management experienced in banking in the markets First Financial serves. First Financial’s ability to retain executive officers and the current management teams will continue to be important to successful implementation of First Financial’s strategies. First Financial does not have employment agreements with these key employees other than executive agreements in the event of a change of control and a confidential information, non-solicitation and non-competition agreement related to First Financial’s stock options. The unexpected loss of services of any key management personnel, or the inability to recruit and retain qualified personnel in the future, could have an adverse effect on First Financial’s business and financial results.

First Financial may not be able to attract and retain skilled people.

First Financial’s success depends, in large part, on its ability to attract and retain key people. Competition for the best people in most activities engaged in by First Financial can be intense and First Financial may not be able to hire people or to retain them. The unexpected loss of services of one or more of the Corporation’s key personnel could have a material adverse impact on First Financial’s business because of their skills, knowledge of First Financial’s market, years of industry experience and the difficulty of promptly finding qualified replacement personnel.

First Financial’s stock price can be volatile.

Stock price volatility may make it more difficult for you to resell your common stock when you want and at prices you find attractive. First Financial’s stock price can fluctuate significantly in response to a variety of factors including, among other things:

General market fluctuations, industry factors and general economic and political conditions and events, such as economic slowdowns or recessions, interest rate changes or credit loss trends could also cause First Financial’s stock price to decrease regardless of operations results.

Breakdowns in First Financial’s internal controls and procedures could have an adverse effect on First Financial.

First Financial believes its internal control system as currently documented and functioning is adequate to provide reasonable assurance over its internal controls. Nevertheless, because of the inherent limitation in administering a cost effective control system, misstatements due to error or fraud may occur and not be detected. Breakdowns in First Financial’s internal controls and procedures could occur in the future, and any such breakdowns could have an adverse effect on First Financial.

First Financial competes in an industry that continually experiences technological change, and First Financial may have fewer resources than many of its competitors to continue to invest in technological improvements.

The financial services industry is undergoing rapid technological changes, with frequent introductions of new technology-driven products and services. In addition to improving the ability to serve customers, the effective use of technology increases efficiency and enables financial institutions to reduce costs. Our future success will depend, in part, upon First Financial’s ability to address the needs of its customers by using technology to provide products and services that will satisfy customer demands for conveniences, as well as to create additional efficiencies in its operations. Many of First Financial’s larger competitors have substantially greater resources to invest in technological improvements. First Financial may not be able to effectively implement new technology-driven products and services or be successful in marketing these products and services to its customers.

System failure or cybersecurity breaches of First Financial’s network security could subject it to increased operating costs as well as litigation and other potential losses.

The computer systems and network infrastructure First Financial uses could be vulnerable to unforeseen hardware and cybersecurity issues. First Financial’s operations are dependent upon its ability to protect its computer equipment against damage from fire, power loss, telecommunications failure or a similar catastrophic event. Any damage or failure that causes an interruption in First Financial’s operations could have an adverse effect on its financial condition and results of operations. In addition, First Financial’s operations are dependent upon its ability to protect the computer systems and network infrastructure utilized by it, including its Internet banking activities, against damage from physical break-ins, cybersecurity breaches and other disruptive problems caused by the Internet or other users. Such computer break-ins and other disruptions would jeopardize the security of information stored in and transmitted through First Financial’s computer systems and network infrastructure, which may result in significant liability to it, damage its reputation and inhibit current and potential customers from its Internet banking services. Each year, First Financial adds additional security measures to its computer systems and network infrastructure to mitigate the possibility of cybersecurity breaches including firewalls and penetration testing. First Financial continues to investigate cost effective measures as well as insurance protection.

An investment in First Financial’s common stock is not an insured deposit.

First Financial’s common stock is not a bank deposit and, therefore, is not insured against loss by the FDIC, any other deposit insurance fund, or by any other public or private entity. Investment in First Financial’s common stock is inherently risky for the reasons described in this “Risk Factors” section and elsewhere in this proxy statement/prospectus. As a result, if you acquire First Financial’s common stock, you may lose some or all of your investment.

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 asset salemerger is completed as well as information about the asset sale.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 asset salemerger or First Financial after the asset sale,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 OSB Financial Services, Inc.FBC and is being furnished to all record holders of OSB FinancialFBC common stock in connection with the solicitation of proxies by the board of directors of OSB FinancialFBC to be used at the special meeting of shareholders of OSB Financial OneFBC to be held on July 23, 2015. The purpose of the purposes of the OSB FinancialFBC special meeting is to consider and vote to approve the sale of substantially all of the assets of OSB Financial pursuant to the mergerreorganization agreement, dated February 20, 2013,April 1, 2015, by and between First Financial First Financial Bank, N.A., OSB Financial, and Orange Savings Bank, SSB, which provides,FBC, and the transactions contemplated by the reorganization agreement including, among other things, for the merger of Orange Savings Bank, SSBFBC 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 Bank, N.A. Financial.

This document also constitutes a prospectus relating to the First Financial common stock to be issued to OSB Financialshareholders of FBC common stock upon completion of the asset sale and the merger, and subsequently to holders of OSB Financial pursuant to a distribution of the consideration it receives in the asset sale.merger.

OSB FINANCIALFBC SPECIAL SHAREHOLDERS’ MEETING

Date, Place and Time of the Special Meeting

The special meeting of shareholders of OSB Financial Services, Inc.FBC will be held on [                    ], 2013July 23, 2015 at [    ] [    ].m.1:00 p.m., local time, in the lobby of Orange Savings Bank, SSB at 812 North 16^th Street, Orange,FBC’s office located at 1800 West White Oak Terrace, Conroe, Texas 77630,77304. The special meeting may be postponed to another date or place for proper purposes, including for the following purposes.purpose of soliciting additional proxies.

Matters to be ConsideredPurpose

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

At this time, the board of directors of OSB FinancialFBC 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 Quorum and Vote Required

The close of business on June 19, 2015 is the record date. The holders of record of the outstanding shares of OSB FinancialFBC common stock atas of the close of business on [                    ], 2013the record date are entitled to notice of, and to vote at, the special meeting.meeting, or any postponement thereof. At the close of business on thatthe record date, there were 274,668884,600 shares of OSB FinancialFBC common stock outstanding and entitled to vote at the special meeting.

At the special meeting, the shareholders of OSB FinancialFBC will be entitled to one vote for each share of common stock owned as of the close of business on the record on [                    ], 2013. date.

Quorum; Vote Required

The holders of a majority of the shares of OSB FinancialFBC 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. TheApproval of the reorganization agreement requires the affirmative vote of the holders of at least two-thirds of the outstanding OSB Financialshares of FBC common stock is requiredentitled to approve the asset sale pursuant to the merger agreement.

Abstentions and shares held of record by a broker or nominee that are voted on any matter are included in determining whether a quorum exists at the special meeting. Brokers, as holders of record, are permittedvote. If you fail to vote, on certain routine matters, but not on non-routine matters. The proposal to approveit will have the asset sale pursuant toeffect of a vote against the merger agreement is a non-routine matter. Accordingly, if a shareholder holds shares through a broker or nominee, also referred to as held in “street name” and does not provide voting instructions to his broker orreorganization agreement.

nominee, those shares will not be voted on the proposal to approve the asset sale pursuant to the merger agreement at the special meeting. Accordingly, the board of directors of OSB Financial Services encourage you to complete, date and sign the accompanying proxy card and return it promptly in the enclosed postage-paid envelope.

Shares Held by OfficersDirectors and DirectorsExecutive Officers

OnAs of the record date, all of the directors of FBC (5 persons) and executive officers of OSB FinancialFBC were entitled to vote in the aggregate, 84,744232,051 shares of OSB FinancialFBC common stock, or approximately 30.85%26.2% of the outstanding shares of OSB Financialthe common stock.stock entitled to vote at the special meeting. Each of thesethe directors and executive officers has executed an agreementa 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 OSB FinancialFBC common stock in favor of approval of the asset salemerger pursuant to the mergerreorganization agreement.

The board In addition to the directors, certain shareholders of directorsFBC have entered into the voting agreement. As of OSB Financial unanimously recommends that youthe record date, 714,098 shares of FBC common stock, or approximately 80.7% of the outstanding shares of FBC common stock entitled to vote FORat the proposal to approveFBC special meeting, are bound by the asset salevoting agreement. Accordingly, approval of the merger pursuant to the merger agreement.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 OSB Financial or the voting representatives, as applicable,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 asset salemerger pursuant to the mergerreorganization 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 OSB FinancialFBC 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: OSB Financial, 812 North 16^th Street, Orange,FBC Bancshares, Inc., 1800 West White Oak Terrace, Conroe, Texas 77630,77304, Attention: Secretary. If you hold your shares in street name with a brokerage firm, bank, trust or broker,other nominee, you must contact such brokerage firm, bank, trust or brokerother 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 OSB Financial. OSB FinancialFBC. 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 OSB FinancialFBC intend to solicit proxies personally or by telephone or other means of communication. The directors will not be additionally compensated. OSB FinancialFBC 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 ASSET SALE AND MERGERTHE REORGANIZATION AGREEMENT

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

Terms of the Asset SaleMerger

Structure of Merger. The asset sale will be accomplishedreorganization 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 merger agreement, which provides for, among other things, the merger of Orange Savings Bank, SSB with and into First Financial Bank, N.A. If the shareholders of OSB Financial approve the asset sale pursuant to the mergerreorganization agreement at the special meeting, and if(ii) the required regulatory approvals are obtained and (iii) the other conditions to the parties’ obligations to effect the asset sale andtransactions contemplated by the related mergerreorganization agreement are met or waived by the party entitled to do so, we anticipate that the asset saletransactions contemplated by the reorganization agreement will be completed in the second quarter of 2013,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 asset sale, OSB Financialmerger, 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, cash. Subsequentin 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 completionreorganization 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 asset sale, OSB Financial intends to distribute mostbank merger, the existing branches and main office of the consideration it receives to its shareholders, other than dissenting shareholders, subject to OSB Financial’s obligation under the merger agreement to maintain ownership of cash or other assets (other than sharesFirst Bank will become branches of First Financial common stock) with a net fair market valueBank.

Consideration. The number of at least $1,000,000 in excess of any liabilities of OSB Financial until December 30, 2013.

In connection with the asset sale and pursuant to the merger agreement, all outstanding shares of Orange Savings Bank, SSB common stock will be converted into an aggregate of 420,000 shares of First Financial common stock and $39.2 million in cash, withdeliverable for each share of FBC common stock will be determined based on the cash portionaverage daily closing price of First Financial’s common stock on the NASDAQ Global Select Market for each of the consideration subject to decreasetwenty consecutive trading days ending on a dollar-for-dollar basis, in the manner set forth infifth business day immediately preceding the closing date of the merger, agreement and discussed below, if Orange Savings Bank, SSB’s equity capital onreferred to as the Calculation Date is less than $43.2 million.

If Orange Savings Bank, SSB’s equity capital as of the Calculation Date is less than $43.2 million, the cash portion of the consideration payable to OSB Financial will be reduced by an amount equal to the difference between Orange Savings Bank, SSB’s equity capital on the Calculation Date and $43.2 million. Pursuant“FFIN Market Price” in this proxy statement/prospectus. Subject to the terms of the mergerreorganization agreement, equity capitalthe general method for calculating the number of Orange Savings Bank, SSB means the sum of the capital stock, capital surplus and retained earnings of Orange Savings Bank, SSB, excluding unrealized securities gains or losses, on a consolidated basis, as determined pursuant to GAAP, with such amountsshares to be calculated in accordance withissued for each share of FBC common stock is to divide the methodology usedaggregate 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 Orange Savings Bank, SSB Reportreorganization agreement, the aggregate merger consideration will be determined as follows:

After completion of the asset sale, OSB Financial intends to distribute the consideration it receives, after repayment of its obligations and expenses, including repayment of all of its outstanding trust preferred promissory notes and 2009 Senior Secured Notes Due December 31, 2020, to the holders of the OSB common stock, other than dissenting shareholders, subject to OSB Financial’s obligation under the merger agreement to maintain ownership of cash or other assets (other than shares of First Financial common stock) with a net fair marketstock 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 at least $1,000,000shares of First Financial common stock equal to the FFIN Share Cap, First Financial may, in excess of any liabilities of OSB Financial until December 30, 2013.

Becauseits sole discretion, (i) increase the number of shares of First Financial common stock to be issued in the asset sale is fixed, the value of the total consideration you will receive, by virtue of the distribution of such consideration by OSB Financial after consummation of the asset sale, will fluctuate based on the market price of the First Financial common stock. Further, the cash portion of the consideration is subject to decrease as described above and in the merger agreement. Accordingly, you will not know the exact amount of cash or the value of the stock portion of the consideration OSB Financial will receive in connection with the asset sale when you vote on the asset sale and the merger agreement. Moreover, any distribution to shareholders of OSB must be authorized by the board of directors of OSB Financial

Background of the Asset Sale

Since the recession of 2008-2009, there have been significant changes in the banking and financial services industry. These developments have included increased emphasis and dependence on automation, specialization of products and services, increased competition among financial institutions, and a trend toward consolidation. Furthermore, an increase in regulatory compliance costs coupled with a prolonged low interest rate environment have created headwinds for generating traditional bank earnings. Based on these developments, management of OSB Financial had determined that size and scale would aid in driving efficiencies, and the introduction of additional products would help the Orange Savings Bank, SSB serve more of its customers’ financial needs. Management of OSB Financial believed these advancements would be needed to produce satisfactory earnings relative to required regulatory capital for Orange Savings Bank, SSB going forward in this challenging operating environment.

Management of OSB Financial considered the costs and requirements for Orange Savings Bank, SSB to add the infrastructure and human capital needed to pursue significantly greater size and scale in addition to introducing additional products like trust and investment services. In summary, it was determined that OSB Financial needed to either invest substantially into a platform for additional products and technology, or it needed to merge with a strategic partner that already had those capabilities. Furthermore, management of OSB Financial believed that these considerations should also be evaluated in conjunction with the availability and timing of liquidity for shareholders of OSB Financial.

The board of directors of OSB Financial established a special committee to further evaluate these considerations (the “Capital Committee”). The Capital Committee included Stephen Lee, OSB Financial’s President, in addition to directors, Thomas Gunn, Paul Peveto and Ross Smith. On June 12, 2012, representatives of Hovde met with the Capital Committee. During that meeting, discussions covered the strategic alternatives available to OSB Financial for maximizing shareholder value including, among other things, continued independence or a strategic merger or affiliation with another financial institution. After this meeting, the Capital Committee decided to engage a financial advisor to pursue an affiliation with a strategic partner.

On July 12, 2012, OSB Financial engaged Hovde to render financial advisory and investment banking services in connection with a possible business combination with another banking institution.

During the next week, management of OSB Financial compiled the items necessary for Hovde to prepare a confidential information memorandum presenting data on OSB Financial and its business. Working with Hovde, a process was developed to contact and elicit interest from a group of logical prospective strategic partners who would be provided the memorandum, subject to the prior execution of a confidentiality agreement. Management expressed interest in First Financial among the parties contacted. In late July, Hovde, began contacting potential strategic partners, including First Financial, and distributed confidentiality agreements to those who expressed an initial interest.

During the month of August 2012, the confidential information memorandum was sent to the twelve parties who had executed confidentiality agreements.

By September 10, 2012, Hovde had received feedback from the prospective strategic partners who had received the confidential information memorandum.

September 12, 2012, a call was held with representatives of Hovde and the Capital Committee to evaluate the interest. Of the parties contacted, three expressed an interest in continued discussions, including First Financial. The second party (“Party B”) orally expressed an interest to pursue an acquisition of the Orange Savings Bank, SSB for approximately $44-46 million. First Financial and the third party (“Party C”) expressed an interest to meet with management but did not provide a value at that time.

The Capital Committee asked for Hovde to arrange meetings with management from First Financial and Party C, and determined that the oral expression of interest from Party B did not warrant further discussion.

On October 3, 2012, management of First Financial met with the Capital Committee in Orange, Texas.

During October 2012, representatives of Hovde had several calls with management of First Financial to discuss the parameters of a potential transaction.

October 31, 2012, First Financial presented a letter of intent to acquire Orange Savings Bank, SSB for $56 million in stock and cash based upon the Orange Savings Bank, SSB’s equity at September 30, 2012, of $44.43 million.

By November 1, 2012, management of Party C had orally communicated that it would be unable to evaluate a potential transaction until late in the first quarter of 2013 and this timing could not be confirmed with certainty.

November 5, 2012, Hovde had a call with the Capital Committee to evaluate and discuss the terms of the letter. The Capital Committee stated it was prepared to move forward with First Financial if the required closing equity for Orange Savings Bank, SSB was established at $43.2 million and any equity in excess of this amount could be paid out prior to closing as a dividend to OSB Financial.

November 7, 2012, First Financial presented a revised letterthe FFIN Share Cap, (ii) increase the number of intent to OSB Financial based upon these terms and the Capital Committee authorized Stephen Lee to execute the letter calling for a period of exclusive due diligence and negotiations with First Financial.

On November 16, 2012, Larry Temple was contacted and retained as legal counsel to advise and represent OSB Financial in potential negotiations.

On November 11-12, 2012, the Capital Committee and representatives of Hovde met with management of First Financial in Abilene, Texas, and a schedule was established for due diligence. In late November and early December 2012, First Financial conducted its due diligence review in Orange, Texas.

On December 18, 2012, First Financial circulated an initial draft of a merger agreement to OSB Financial’s counsel, Larry Temple. Negotiations regarding the draft merger agreement continued into January 2013.

On January 8, 2013, a meeting was held in Dallas with management of First Financial and OSB Financial, in addition to representatives of Hovde, and the parties’ respective legal counsel were present. Several aspects of the draft merger agreement were discussed at length.

During the following weeks, negotiations continued and it was determined that the stock consideration would equate to 420,000 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 cash consideration that would be $39.2 million. Additionally, it was determinedpayable 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 being issued wouldtrades 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 registered withpaid pursuant to the SEC.

From February 1, 2013 through February 20, 2013, OSB Financial reviewedreorganization agreement will be reduced on a dollar-for-dollar basis in the termsevent 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 preparedhave been made, is less than $14,705,000.

Dividend of Excess Shareholders’ Equity. To the appropriate schedules,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 retention bonus agreements were executed with certain employeesmay 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 Orange Savings Bank, SSB.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.

OnBackground of the morning of February 20, 2013, the OSB FinancialMerger

The FBC board of directors metperiodically has reviewed FBC’s performance, compared its performance with representativesthat of Hovde. Hovde provided a financial analysis ofcertain comparable institutions, reviewed the proposed transactionlimited market activity in FBC’s common stock, considered various business opportunities and informedstrategies available to FBC and discussed the OSB Financialgeneral economic, regulatory, competitive and business pressures affecting FBC and First Bank. In addition, the FBC board of directors, that the proposed consideration set forthon 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 agreement is fair totransaction, including a preliminary price range. On October 15, 2015, representatives of Vining Sparks provided FBC with its initial analysis regarding the shareholders

preliminary pricing range and structure offered by First Financial, which analysis discussed the attractiveness of OSB Financialthe 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 asset sale,transactions contemplated by the mergerreorganization agreement, authorized the execution of the reorganization agreement and recommended the approval of the reorganization agreement and the merger and authorizedtransactions contemplated therein to the Presidentshareholders of OSB Financial to execute the merger agreement on behalf of OSB Financial Shortly thereafter,FBC.

On April 1, 2015, First Financial and OSBFBC 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 proposed merger.transaction.

Recommendation of OSB Financial’sFBC’s Board and its Reasons for the Asset SaleMerger

OSB Financial’sFBC’s board of directors believes that the asset salemerger is in the best interest of OSB FinancialFBC and its shareholders. Accordingly, OSB Financial’sFBC’s board of directors has unanimously approved the asset sale, the related merger and the mergerreorganization agreement and unanimously recommends that OSB FinancialFBC’s shareholders vote FOR approval of the asset sale and the mergerreorganization agreement.

In approving the asset sale and the mergerreorganization agreement, OSB Financial’sFBC’s board of directors consulted with its financial advisorVining Sparks with respect to the financial aspects and fairness of the proposed merger transactionconsideration, 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 merger agreement and related agreements.reorganization agreement. The board believes that combining with First Financial will create a financially sounderstronger and more diversified organization that will provide significant benefits to OSB Financial’sFBC’s shareholders and customers alike.

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