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REVIEW YOUR PROXY STATEMENT AND VOTE IN ONE OF THESE FOUR WAYS:
	Vote Online  ·Before the Meeting: Go towww.proxyvote.com ·     During the Meeting: Go towww.virtualshareholdermeeting.com/ffbc16		Vote by Phone By calling 1-800-690-6903
	Vote by Mail  By signing, dating, and returning your proxy card in the enclosed envelope		Vote in Person By attending the Annual Meeting

ELECTRONIC DELIVERY OF FUTURE PROXY MATERIALS

If you would like to help us reduce our costs incurred in mailing proxy materials, you can consent to receiving all future proxy statements, proxy cards and annual reports electronically via e-mail or the Internet. To sign up for electronic delivery, please follow the instructions above to vote using the Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in future years.

Mailing Date:      April 14, 2016	BY ORDER OF THE BOARD OF DRECTORS
	Shannon M. Kuhl
	Corporate Secretary

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PROXY STATEMENT Mailing Date: April 14, 2016

We are sending this proxy statement and the accompanying proxy card to you as a shareholder of First Financial Bancorp., an Ohio corporation, in connection with the solicitation of proxies for the 2016 Annual Meeting of Shareholders (the “Annual Meeting”). Our Board of Directors is soliciting proxies for use at the Annual Meeting, or at any postponement or adjournment of the Annual Meeting.

Meeting Agenda and Voting Recommendations:

Proposal	Approval Required	Board’s Recommendation	Page Reference
1.   Election of Directors	Affirmative vote of a plurality	For Each Nominee	6
2.   Re-approval of the Amended and Restated Key Executive Short Term Incentive Plan	Majority of votes present, in person or by proxy, and entitled to vote	For	11
3.   RatifyIf you would like to help us reduce our costs incurred in mailing proxy materials, you can consent to receiving all future proxy statements, proxy cards and annual reports electronically via e-mail or the appointment of Crowe Horwath LLP as our independent registered public accounting firmInternet. To sign up for 2016	Majority of votes present, in person or by proxy, and entitledelectronic delivery, please follow the instructions above to vote	For	13
4.   Approve, on an advisory basis, using the compensation of the Company’s executive officers	Majority of votes present,Internet and, when prompted, indicate that you agree to receive or access proxy materials electronically in person or by proxy, and entitled to vote	For	15future years.

​	​	​	​	​	​	​	​	​
Proposal				Approval Required		Board's Recommendation		Page Reference
​	​	​	​	​	​	​	​	​
1.		Election of Directors		Affirmative vote of a plurality		For Each Nominee		8
2.		Ratify the Appointment of Crowe LLP as our Independent Registered Public Accounting Firm for 2019		Majority of votes present, in person or by proxy, and entitled to vote				17
3.		Approve, on an Advisory Basis, the Compensation of the Company's Executive Officers		Majority of votes present, in person or by proxy, and entitled to vote				19
​	​	​	​	​	​	​	​	​

We are not aware of any other matters that will be brought before the shareholders for a vote at the Annual Meeting. If any other matter is properly brought before the meeting, your completed proxy may, if you have so selected, give your proxies the authority to vote on these other matters in their best judgment.

In this proxy statement, the “Company,” “First"Company," "First Financial,” “First" "First Financial Bancorp,” “we,” “our,”" "we," "our," or “us”"us" all refer to First Financial Bancorp. and its subsidiaries.subsidiaries, unless the context otherwise requires. We also refer to the Board of Directors of First Financial as the “Board.”"Board." References in this proxy statement to “common shares”"common shares" or “shares”"shares" refer to the Company’sCompany's common shares.

Unless otherwise noted, the information in this proxy statement covers our 20152018 fiscal year that began January 1, 20152018 and ended December 31, 2015.2018.

Review the proxy statement and vote in one of these three ways:

Vote Online		Vote by Phone				Vote by Mail
■ Before the Meeting: Go to www.proxyvote.com ■ During the Meeting: Go to www.virtualshareholdermeeting.com/ffbc19		By calling            1-800-690-6903				By signing, dating, and returning your                      proxy card in the enclosed envelope

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The first item of business at the Annual Meeting will be the election of fifteen directors of the Company. The nominees, including their occupation and committee memberships during 2018, are set forth in the table below.

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2018 was a transformational year for the Company. In April 2018, we completed the merger with MainSource Financial Group, an Indiana-based bank holding company. As a result of the merger, the Company grew by $4.4 billion in assets, $2.8 billion in loans and $3.3 billion in deposits. Following the merger, our Board was reconstituted with nine former members of the Company's board and six former members of MainSource's board. We also reorganized our executive team, with our former Chief Executive Officer becoming Executive Chair and MainSource's former President and Chief Executive Officer becoming President and Chief Executive Officer of the Company. Notwithstanding these significant changes, the Company continued its pattern of excellent profitability, as discussed in the business highlights on page 34 of this proxy statement.

1.

Non-GAAP financial measure which management believes facilitates a better understanding of the Company's financial condition. See Appendix A for Non-GAAP reconciliation.

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Proxy Statement Information

Why am I receiving this Proxy Statement?

We are making available this Notice of Annual Meeting of Shareholders, proxy statement, and annual report for the year ended December 31, 20152018 (the “proxy materials”"proxy materials"), either online or by mail, in connection with the 20162019 Annual Meeting of Shareholders of First Financial because you are a shareholder of record of the Company as of the close of business on March 30, 2016April 1, 2019 (the “record date”"record date"). This proxy statement describes the matters on which you are asked to vote and provides information about those matters and about the Company so that you can make an informed decision.

This proxy statement and related materials are being mailed to, or can be accessed online by, shareholders on or about April 14, 2016.18, 2019.

What is Notice and Access and why did First Financial elect to use it?

We are making the proxy materials and annual report available to our shareholders electronically via the Internet under the Notice and Access regulations of the U.S. Securities and Exchange Commission (“SEC”("SEC"). Many of our shareholders have received a Notice of Internet Availability of Proxy Materials (“("Notice of Internet Availability”Availability") in lieu of receiving a full set of printed materials in the mail. We are using the Notice and Access method to expedite distribution and reduce the costs associated with printing and mailing these materials.

The Notice of Internet Availability includes information on how to access and review the proxy materials and how to vote online, by phone, or by attending the Annual Meeting.Meeting virtually via the Internet. The proxy materials and annual report, as well as other reports filed with or furnished to the SEC, can be accessed free of charge atwww.bankatfirst.com/investor.investor. You may also access this information by searching “Company Filings”"Company Filings" atwww.sec.gov. www.sec.gov.

I received a Notice of Internet Availability of Proxy Materials only. How can I receive printed copies of the proxy statement and annual report?

Shareholders may receive a printed copy of the annual report and proxy materials, free of charge, by following the instructions on the Notice of Internet Availability for receiving such materials:

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How do I vote my shares?

Even if you plan to attend the Annual Meeting in person or virtually via the Internet, as described below, we strongly encourage you to vote prior to the meeting. Shareholders of record may vote using any of the following methods:

Online Voting:  You may vote before or during the meeting through the Internet as instructed on your Notice of Internet Availability or proxy card. Before the Annual Meeting, you may go tohttp://www.proxyvote.com to transmit your voting instructions up until 11:59 p.m. Eastern Time on May 23, 2016.27, 2019. During the meeting, you may go towww.virtualshareholdermeeting.com/ffbc16ffbc19 to attend the meeting via webcast and vote online. You should have your proxy card or Notice of Internet Availability in hand when you access either of these websites and follow the instructions to obtain your records and to vote.

Vote by Phone:  Telephone voting is available toll-free at 1-800-690-6903 up until 11:59 pm Eastern Time on May 23, 2016.27, 2019. You should have your proxy card or Notice of Internet Availability or proxy card in hand when making this call.

Vote by Mail:  Complete, sign and date your proxy card and return it in the envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717.

Vote in Person Proxy cards must be received by Attending the Annual Meeting: Please see the question and answer “How can I attend the Annual Meeting?”provided below for additional information.11:59 p.m. Eastern Time on May 27, 2019.

If you hold your shares in “street name”"street name" at a bank, broker or other nominee, you should follow the instructions provided by your bank, broker or other nominee on how to vote your shares.

What is the difference between holding shares directly as a shareholder of record and holding shares in “street name” at a bank, broker or other nominee?

Shareholder of Record:  If your shares are registered directly in your name with our transfer agent, Computershare Shareholder Services, you are considered the shareholder of record and the proxy materials or a Notice of Internet Availability were sent directly to you. As the shareholder of record, you have the right to grant your voting proxy directly by using the enclosed proxy card, through the online voting methods described in this proxy statement, or by phone, or to vote in person atby voting electronically during the Annual Meeting.

Holding shares in “street name”"street name" at a bank, broker or other nominee:  If your shares are held by a bank, broker or other nominee, you are considered the beneficial owner of shares held in “street"street name.”" The proxy materials, Notice of Internet Availability, or voting instruction card was forwarded to you by your bank, broker or other nominee who is considered the shareholder of record of your shares. Your bank, broker or other nominee will send you, as the beneficial owner, separate information describing how you can vote your shares.

What happens if I sign, date and return my proxy card, or complete the online or telephonic proxy methods, but do not specify how I want my shares voted on one or more of the proposals?

Your shares will be voted in the manner you specify on each proposal. If you are a shareholder of record and completesign, date and return a proxy or submit a proxy online or by telephone, but do not provide voting instructions on one or more proposals, your vote will be counted as a vote “for”"for" all of the Company’sCompany's nominees for directors and for"for" Proposals 2 3 and 4.

3.

If you hold your shares in “street name”"street name" and have not returned voting instructions on one or more proposals, your bank, broker or nominee may vote your shares only on those proposals for which it has discretion to vote. We believe that under applicable rules, your bank, broker or nominee has discretion to vote your shares on routine matters such as the ratification of our independent registered accounting firm Proposal 3.(Proposal 2), which is considered a routine matter. However, your bank, broker or nominee does not have discretion to vote your shares on certain other matters considered non-routine matters such as the election of directors (Proposal 1) or Proposals 2 and 4.the advisory approval of executive compensation (Proposal 3). If you do not provide voting instructions on a non-routine proposal, your shares will be considered “broker"broker non-votes.”" The effect of a “broker non-vote”"broker non-vote" on each proposal is detailed in the questions and answers concerning “Annualunder the heading "Annual Meeting Information”Information" below.

What if I indicate “Withheld” with respect to the election of one or more directors or “Abstain” with respect to any of the other proposals being considered?

The effect of these voting specifications on each proposal is detailed in the questions and answers under the heading “Annual"Annual Meeting Information”Information" below.

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If you “abstain” on a proposal, your shares will be counted for purposes of whether a quorum exists but will otherwise have the same effect as a vote against each proposal for which you abstain.

Can I change my proxy vote?

You may revoke your proxy at any time before it is actually exercised at the Annual Meeting by:

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Sending a written notice of revocation to First Financial Bancorp, Attn: Karen B. Woods, Corporate Secretary, 255 East Fifth Street, Suite 2900, Cincinnati, Ohio 45202;



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Delivering a later dated proxy (including by using the online or telephone voting methods); or



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Attending the virtual Annual Meeting and giving notice of revocation electronically during the meeting.

If you hold your shares in “street name”"street name" and instructed your bank, broker or other nominee to vote your common shares and you would like to revoke or change your vote, you must follow the instructions provided by your bank, broker or other nominee.

What if my shares are held through the First Financial Bancorp 401(k) Savings Plan (applicable to traditional or Roth contribution plans)?

You will receive an electronic Notice of Internet Availability unless you opted to receive paper copies of the proxy materials. The Notice of Internet Availability will contain voting instructions for all shares registered in the exact same name, whether inside or outside of the First Financial Bancorp 401(k) Savings Plan (the “Savings Plan”"Savings Plan"). If you hold shares outside of the Savings Plan and they are not registered in the same name as those within the Savings Plan, you will receive a separate Notice of Internet Availability or proxy card for the shares held outside of the Savings Plan.

Voting instructions with respect to shares held in the Savings Plan must be received by 11:59 pm Eastern Time on May 22, 2016.23, 2019. All voting instructions you give with respect to these shares will be kept confidential. If you do not timely submit voting instructions for these shares, the shares allocated to you, together with all unallocated shares held in the Savings Plan, will be voted in accordance with the pro-rata vote of participants in the Savings Plan who did provide instructions.

Who should I contact if I have questions about this proxy solicitation and where can I get assistance in voting my shares?

You may contact us atshareholderrelations@bankatfirst.com InvestorRelations@bankatfirst.com or call our Investor Relations department toll free at 1-877-322-9530 if you have any questions or need assistance in voting.

Annual Meeting Information

How many votes must be present in person or by proxy to hold the Annual Meeting?

A quorum must exist before business can be conducted at the Annual Meeting. Under our Amended and Restated Regulations (the “Amended Regulations”"Amended Regulations"), a quorum will exist if a majority of the common shares outstanding as of the record date are present in person or by proxy. At the close of business on March 30, 2016,April 1, 2019, there were61,855,021were 98,611,921 common shares outstanding. A majority, or 30,927,51249,305,962 common shares, present in person or by proxy, will constitute a quorum.

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What proposals are being considered and how many votes are needed for each proposal to be approved by the shareholders?

How can I attend the Annual Meeting?

You can attend our 20162019 Annual Meeting in person, via the Internet or by proxy.

Our 20162019 Annual Meeting will take place at our principal executive offices at 255 East Fifth Street, Room 950, Cincinnati, Ohio. You will need to present photo identification, such as a driver’s license, and proof of share ownership as of the record date, such as an account statement or copy of the proxy card or Notice of Internet Availability with your printed name and address, for admission to the Annual Meeting. If you hold your shares in “street name” and you wish to be able to vote at the Annual Meeting, you must obtain and follow instructions provided by the bank, broker or other nominee who is the record holder of the shares. Cameras, recording devices, and other electronic devices will not be permitted at the Annual Meeting.

You may also attend the Annual Meeting via a webcast atwww.virtualshareholdermeeting.com/ffbc16.ffbc19. You may vote while attending the webcast meeting by following the instructions atwww.virtualshareholdermeeting.com/ffbc16.ffbc19. You will not be able to submit questions to executive management or the Board via this webcast during the Annual Meeting. To attend the Annual Meeting viawww.virtualshareholdermeeting.com/ffbc16,ffbc19, you will need the control number included on the Notice of Internet Availability or proxy card that was mailed to you. Instructions on how to attend and participate in the Annual Meeting via the Internet are posted atwww.virtualshareholdermeeting.com/ffbc16.ffbc19.

How do I find out the voting results from the Annual Meeting?

We plan to announce preliminary voting results at the Annual Meeting and will disclose the final voting results in a current report on Form 8-K filed with the SEC within four business days of the Annual Meeting.

Electronic Delivery of Proxy Statement and Annual Report

Can I elect to only receive First Financial’s proxy materials and annual reports electronically?

Shareholders can elect to viewreceive future proxy materials and annual reports electronically instead of receiving print copies of these items in the mail. You can make this election by following the instructions provided on your proxy card or Notice of Internet Availability or by going towww.proxyvote.com and following the instructions provided there.

If you choose to receive future proxy statements and annual reports electronically and you continue to hold shares as of the record date of the next annual meeting, you will receive an e-mail message next year that includes access information for these materials as well as instructions for online voting.

Householding Information

What is “householding?”

If two or more shareholders reside at the same address and appear to be members of the same family, we may send a single copy of the proxy materials, or Notice of Internet Availability, to that address unless one of the shareholders at that address notifies us that they wish to receive individual copies of the material. This procedure reduces our printing and mailing costs. Shareholders who participate in householding will continue to have access to and utilize separate proxy voting instructions for each shareholder account.

How do I stop participating in the householding program?

To stop participating in the householding program, contact Broadridge Financial Solutions, Inc.Householding Department by calling toll free at 1-800-542-10611-866-540-7095 or by writing to Broadridge, Financial Solutions, Attn: Householding Department, 51 Mercedes Way, Edgewood, NY 11717. You will be removed from the householding program within 30 days of Broadridge’sBroadridge's receipt of your instruction.

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Our Board currently consists of fourteenfifteen members, thirteen of whom are non-employee directors. Our Amended Regulations provide that the Board shall consist of not less than nine nor more than 25 persons, with the exact number to be fixed and determined from time to time by resolution of the Board or by resolution of the shareholders at any annual or special meeting of shareholders. Any vacancy may be filled by the Board in accordance with law and our Amended and Restated Regulations for the remainder of the term of the vacant directorship. The Board has established the number of directors at fourteen. Mark A. Collar has chosen not to stand for re-election, and the Board has not appointed a nominee to fill Mr. Collar’s seat on the Board. As a result, the Board has determined that it will decrease the number of directors to thirteen immediately following the Annual Meeting.

fifteen.

Our Board has approved the nomination of the following thirteenfifteen persons as candidates for election as director, each for a one-year term: J. Wickliffe Ach, David S. Barker,Kathleen L. Bardwell, William G. Barron, Vincent A. Berta, Archie M. Brown, Jr., Cynthia O. Booth, Claude E. Davis, Corinne R. Finnerty, Peter E. Geier, Murph Knapke,Erin P. Hoeflinger, Susan L. Knust, William J. Kramer, Jeffrey D. Meyer, John T. Neighbours, Thomas M. O'Brien, Richard E. Olszewski, and Maribeth S. Rahe. Each of the nominees is an incumbent director. The Corporate Governance and Nominating Committee (“CGNC”("CGNC") recommended all thirteenfifteen nominees to the Board, which in turn unanimously approved the nomination of all thirteenfifteen persons.

In the event that any one or more of the nominees becomes unavailable or unable to serve as a director prior to the Annual Meeting, the accompanyingyour submitted proxy will be voted to elect the remaining nominees and any substitute nominee or nominees designated by the Board. We have no reason to believe that any nominee will be unable or decline to serve as a director.

The thirteenfifteen nominees for director receiving the most votes at the Annual Meeting will be elected as directors. You can find additional information about our Policy on Majority Voting in the Corporate Governance section of this proxy statement. The general considerations and criteria for assessing director candidates are established in the Charter of the Board’sBoard's Governance and Nominating Committee (available atwww.bankatfirst.com/investor). These considerations and criteria are also summarized in the Corporate Governance section of this proxy statement.

Below is information concerning the nominees for directors, such asincluding their present and past professional positions, current directorships with other companies or organizations, and key qualifications and attributes qualifying them to serve on our Board. The age indicated for each nominee below is their age as of March 30, 2016.April 1, 2019. For information regarding ownership of shares of the Company by nominees and directors of the Company, see the Shareholdings of Directors, Executive Officers and Nominees for Director section of this proxy statement. Except as noted, there are no arrangements or understandings between any director or any nominee and any other person pursuant to which such director or nominee is or was nominated to serve as director.

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Mr. Ach recently retired from his role as President and Chief Executive Officer of Hixson Inc., an architectural engineering firm located in Cincinnati, Ohio. He served in this role from 1993 until his retirement on May 31, 2018.

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Mr. Ach is presently the Lead Independent Director of the Board of Directors of First Financial Bancorp. He previously served as the Vice Chair of the Board of Directors.

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Mr. Ach presently serves on the board of directors of Setzer Corp. (a private corporation located in Dayton, Ohio that is a construction contractor) and on the board of trustees of Grote Enterprises (a private construction company located in Cincinnati, Ohio). Mr. Ach also serves on the board of directors of the CISE Foundation, a Cincinnati not-for-profit organization. He is or has been involved in a number of business and civic organizations, including the Cultural Facilities Task Force of Hamilton County, Ohio, relating primarily to the Cincinnati Museum Center and Music Hall facilities. Mr. Ach is President of the Union Terminal Corporation.

As a seasoned business owner and entrepreneur, Mr. Ach brings valuable insight to the Board in strategic and cultural matters. Mr. Ach's involvement in the Cincinnati business community provides added understanding of our growing Cincinnati market area. Furthermore, his specific background in architectural engineering provides added value in our strategies related to physical banking center locations and design.

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Ms. Bardwell currently serves as Senior Vice President, Chief Compliance Officer of STERIS Corporation. In her role she is responsible for Regulatory Affairs, AST Quality Operations, Global Compliance, Corporate Internal Audit and Security and serves as STERIS' chief compliance officer, chief audit executive and on its ethics committee. She brings over 35 years of audit and accounting experience to the Company's Board of Directors.

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Ms. Bardwell is a member of the National Association of Corporate Directors (NACD), the American Institute of Certified Public Accountants (AICPA), the Ohio Society of CPAs (OSCPA), the Institute of Internal Auditors (IIA), the American Society for Quality (ASQ) and AdvaMed. She has been a Certified Public Accountant since 1989 and received a Certification in Risk Management Assurance (CRMA) designation in 2013.

Ms. Bardwell previously served as a director of MainSource Financial Group, Inc. and MainSource Bank, from 2011 until April 1, 2018. Ms. Bardwell's many years of expertise relating to regulatory compliance and financial reporting controls, both of which are vital in the financial services industry, her experience with publicly traded companies, and her qualification as an audit committee financial expert provide valuable insight to the Company.

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Mr. Barron is a commercial-industrial real estate specialist. He has been Chairman and President of Wm. G. Barron Enterprises, Inc., a commercial real estate broker, manager and developer, since June 1994. Since 1997, Mr. Barron has been designated a Certified Commercial Investment Member, which signifies expertise in commercial real estate brokerage, leasing, valuation, asset management and investment analysis.

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In addition, Mr. Barron is President of Owensboro Self Bailment, LLC, a self-storage holding company, and Gunston, LLC, a real estate holding company. Prior to these activities, Mr. Barron served as Vice President (1974-81), President (1981-87) and Chairman and CEO (1987-94) of Barron Homes, Inc., a residential home building company.

Mr. Barron previously served as a director of MainSource Financial Group, Inc. beginning in 1989 and as a director of MainSource Bank from 2011 until April 1, 2018, following prior service on the MainSource Bank board from 1983 to 2000.

Mr. Barron is very active in his community in both civic and charitable positions, including Former Chairman of the Board of the Owensboro Family YMCA, YMCA Endowment Fund Committee, Former Board member of Mentor Kids Kentucky, Board Member and past President of the Owensboro Homebuilders Association, and Board member of Owensboro Daviess County Chamber of Commerce. Mr. Barron has served as President of the Owensboro Rotary Club. Mr. Barron is a graduate of Leadership Owensboro and Leadership Kentucky.

Mr. Barron brings extensive experience in the banking, homebuilding and commercial real estate development industries and a deep commitment to community which provide valuable expertise to the Company.

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Mr. Berta currently serves as the President and Managing Director of Covington Capital, LLC, a private investment firm providing specialized investment banking and advisory services primarily to financial, real estate and investment companies.

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Mr. Berta has 34 years of experience in the financial services industry, previously serving as the Executive Vice President and Regional Chairman of US Bank Corporation, the Chairman, President and Chief Executive Officer of Trans Financial, Inc., a $2.3 billion bank acquired by US Bank Corporation in 1998, and a partner in Landmark Financial Advisors, Inc., a registered investment advisory company he co-founded in 2002. Mr. Berta also served as a chief financial officer and in various other roles for banking institutions. Mr. Berta is active in various community and civic associations, including work on the Focus 2030 Comprehensive Plan, which was formed to provide a community framework for growth in Bowling Green, Kentucky.

Mr. Berta previously served as a director of MainSource Financial Group, Inc. and MainSource Bank from 2016 until April 1, 2018.

Mr. Berta's significant experience in the financial services industry, including specifically his executive experience as an officer of banking institutions, provides valuable insight and knowledge to the Board.

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Ms. Booth is the President of Private Wealth Group, Vice President of Residential Real Estate, Vice President of Human Resources, and Chief Executive Officer of COBCO Enterprises, LLC, the owner and operator of eight McDonald's restaurants in the Cincinnati area. Prior to forming COBCO in 2000, she held various executive positions at Firstar Bank (now U.S. Bank) in Cincinnati, including President, Firstar Bank Foundation, Senior Vice President—Director of Community Development, Vice President of Private Wealth Group, Vice President of Residential Real Estate, Vice President of Human Resources, and before that was President of Diversified Solutions, Inc., a bank consulting firm.

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Ms. Booth is active in several civic and community organizations, including serving as a director and the treasurer of the Greater Cincinnati Regional Chamber of Commerce and as a director of the YWCA of Greater Cincinnati.

Ms. Booth brings deep banking experience to the Board, including extensive knowledge in residential real estate lending, regulatory relations, the Community Reinvestment Act and other regulatory compliance, private banking and human resources matters. Furthermore, her experience in the restaurant franchise area provides valuable insight into the specialty area of lending conducted through our subsidiary First Franchise Capital Corporation.

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Mr. Brown is the President and Chief Executive Officer of First Financial Bancorp. and First Financial Bank, having been appointed to these positions effective April 1, 2018. Previously, he served as the President and Chief Executive Officer of MainSource from August 2008 until April 1, 2018. Mr. Brown also served as the chairman of the board of MainSource from April 2011 until April 1, 2018.

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During his 34 years in banking, Mr. Brown has held management positions in branch management, region management, bank operations (both deposit and loan), business development, small business and consumer lending. Mr. Brown has experience in many areas of banking, including enterprise risk management, change management, expense reduction initiatives, process re-engineering, balance sheet management and restructures, loan workout initiatives, business startups within the bank, business consolidation, market selection, branch and bank acquisitions and integration, board communication, investor and shareholder relations and working with bank regulators.

Mr. Brown serves on the board and executive committee of the Cincinnati City Centre Development Corp (3CDC), is a board member of the Cincinnati Regional Business Committee (CRBC), a board member and incoming 2019 Campaign Chair for United Way of Greater Cincinnati and a director at the Indiana Community Business Credit Corporation. He formerly served as a director of the Indiana Bankers Association, the Indiana Chamber of Commerce and Greensburg Decatur County Economic Development Corporation.

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Mr. Davis is the Executive Chairman of First Financial Bancorp and First Financial Bank effective April 1, 2018. He previously served as the Chief Executive Officer of both First Financial Bancorp and First Financial Bank (2004-2008). Mr. Davis has nearly 30 years of experience in the financial services industry.

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Mr. Davis serves as Chairman of the Brixey Capital Investment Committee, and is on the board of directors of City Dash, a Brixey portfolio company and a Cincinnati-based logistics company, and is on the Cincinnati Regional Economic Development Committee (REDI) and the Cincinnati Business Committee. He previously served on the board of directors of the Federal Reserve Bank of Cleveland from 2013 to 2018.

Mr. Davis' years of experience in the banking industry as well as his extensive financial background provide leadership to the Board. He is intimately familiar with all aspects of our business activities. His involvement on other boards and organizations gives him insight on important societal and economic issues relevant to our Company's business and markets.

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Ms. Finnerty is the principal and sole shareholder of the law firm of McConnell Finnerty PC located in North Vernon, Indiana. She has over 35 years of experience representing financial institutions in a wide variety of legal matters. Ms. Finnerty was previously a director of a former affiliate bank of First Financial from 1987 to 2005 and joined the board of the Company in 1998.

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Ms. Finnerty served as a member of the Indiana Supreme Court Disciplinary Commission from 2003 to 2013. She currently serves as a Commissioner on the Indiana State Ethics Commission, having been appointed to a 4 year term by Indiana's Governor beginning in January 2018.

Ms. Finnerty's deep roots in the North Vernon, Indiana area provide representation on the Board for our southeast Indiana market. Her participation for ten years on the Indiana Supreme Court Disciplinary Commission and her current position as a Commissioner on the Indiana State Ethics Commission allow her to provide insight on governance and ethical issues. Furthermore, her years as a practicing attorney, including the representation of financial institutions for over 35 years, give her an enhanced perspective on legal and regulatory issues.

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Ms. Hoeflinger is a Senior Vice President, Business Strategy and Execution of Aetna, a national, diversified health care benefits company. She is responsible for leading the implementation of Aetna's strategy and connecting it to the operating plans across the Aetna business. She previously served as Senior Vice President of the Commercial Local Business Division of Anthem.

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Ms. Hoeflinger combines her commitment to improving the health of Anthem's members with leadership in civic and business affairs. She currently serves on the Board of Trustees of The Ohio State University and Midmark Corporation. She has an M.B.A. in Business from Xavier University and a B.A. in Communications from Wright State University.

Ms. Hoeflinger previously served as a director of MainSource Financial Group, Inc. and MainSource Bank, from 2015 until April 1, 2018.

Ms. Hoeflinger's extensive experience in executive management of a publicly-traded company in a highly regulated industry is a valuable asset to the Company.

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Ms. Knust is the owner and managing partner or president of several businesses:

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Omega Warehouse Services (since 2002) which is located in Monroe, Ohio and provides public warehousing and manufacturing services;

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K.P. Properties of Ohio (since 1986) which is located in Monroe, Ohio and owns, leases and manages industrial and commercial real estate in Ohio;

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K.P. Properties of Colorado (since 2010) which is located in Monroe, Ohio and owns, leases and manages commercial real estate in Colorado; and

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K.P. Properties of Florida (since 2014) which is located in Monroe, Ohio and owns, leases and manages commercial real estate in Florida.

As a seasoned business owner and entrepreneur for 34 years in the areas of manufacturing, warehousing and industrial real estate, Ms. Knust brings valuable insight to the Board in strategic and other matters. Ms. Knust's business interests are similar in size to our key client base and she also has an understanding of the Cincinnati market. As a female business owner, her perspective and experiences have proven valuable to the Company.

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Mr. Kramer is the Vice President of Operations and a member of the board of directors of Valco Companies, Inc. which has principal offices in New Holland, Pennsylvania and whose principal activity is the design, manufacture, and sale of equipment used in the animal production industry. He has held his current position with Valco Companies, Inc. since 2008, having previously held other executive positions at Valco Companies, Inc. Mr. Kramer was previously a director of a former affiliate bank of First Financial from 1987 to 2005 and joined the board of First Financial in 2005.

Mr. Kramer has been a CPA since 1984 with both public accounting and private company experience providing experience in financial reporting and accounting controls. He qualifies as an audit committee financial expert. Furthermore, his tenure with our Company or a bank affiliate provides valuable historical perspective on both the Company and the banking industry.

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Mr. Neighbours became the General Counsel and an advisor to the board of AmeriQual Group Holdings, a specialty food processing company, located in Evansville, Indiana on January 1, 2018 following his retirement from the law firm of Faegre Baker Daniels. He has practiced law for over 40 years and has represented employers throughout the country in all aspects of labor and employment law. Additionally, he served as an advisor to business, educational and not for profit executives on a variety of business and legal issues.

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Mr. Neighbours is involved in and serves as a director (or in an equivalent position) of a number of non-profit and civic organizations including:

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Greater Indianapolis Chamber of Commerce

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United Way of Central Indiana

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Meadows Community Foundation (Chair)

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Charles A. Tindley Accelerated Schools

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Indianapolis Public Safety Foundation

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Christian Theological Seminary

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Indiana University-Purdue University Indianapolis Advisory Board

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Indianapolis Zoological Society

In addition, he served as a council member for the American Bar Association—Section on Labor and Employment Law for 12 years, as well as chairman of the Developments Under the National Labor Relations Act Committee from 1997 to 2000. He also served on the Labor Relations Committee for the United States Chamber of Commerce.

Mr. Neighbours serves on the board of Real Estate Corporation of America, a family corporation involved in rehabilitating and managing properties in Indianapolis. Also, for the last 10 years, Mr. Neighbours has chaired the Meadows Community Foundation, which has stimulated $70 million of investment in one of Indianapolis' most challenging low income communities, and coordinated the development of mixed income housing, a health complex which includes a YMCA, a retail center and charter schools.

Mr. Neighbours is a recognized leader in the Indianapolis business community, providing valuable insight to the board on the local business environment. His years as a practicing attorney give him an enhanced perspective on legal and employment matters as well the business climate generally given his national practice.

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Mr. O'Brien retired from Procter & Gamble in 2010 after 31 years of service, primarily in management positions in the areas of sales, IT and marketing. Most recently, Mr. O'Brien served as Vice President Customer Business Development, Global Business Units and Global eCommerce from 2007 until his retirement. During his time at Procter & Gamble, Mr. O'Brien developed strategies, conceptual innovations and relationships that consistently delivered successful results in revenue, market share and productivity.

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Mr. O'Brien is currently a senior advisor with the Boston Consulting Group, working with many top consumer product companies on commercial strategies. Mr. O'Brien also currently serves as Chairman of Simpactful Consulting, is a director of One 80 Place and has served on the National Board of Inroads and the St. Vincent De Paul Cincinnati board of directors.

Mr. O'Brien previously served as a director of MainSource Financial Group, Inc. and MainSource Bank from 2010 until April 1, 2018.

Mr. O'Brien's extensive experience in sales and marketing, his management experience, and his experience interacting with the board of directors of a publicly traded company provides valuable perspective to the Board and the Company.

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Mr. Olszewski is the owner and operator of two 7-Eleven Food Store franchises in Griffith, Indiana. He was previously a director of a former affiliate bank of First Financial from 1995 to 2005 and joined the board of the Company in 2005.

Mr. Olszewski's 30 plus years of retail experience and several years of service to our Company provides us with a deeper understanding of our important northwest Indiana market. Furthermore his business and retail experience as a small business owner provides our Company with a better understanding of a key client constituency.

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Ms. Rahe is the President and Chief Executive Officer of Fort Washington Investment Advisors, Inc., positions she has held since 2003. Fort Washington Investment Advisors, Inc. is an investment management firm and wholly owned subsidiary of Western & Southern Financial Group located in Cincinnati, Ohio. She also serves on the board of directors of Fort Washington Investment Advisors, Inc. Ms. Rahe has more than 45 years of experience in the banking and financial services industries with more than 30 years of experience in management or executive management positions.

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Since 2005, Ms. Rahe has served as a director of Consolidated Communications Holdings, Inc. (NASDAQ: CNSL) which is an integrated communication services company located in Mattoon, Illinois that provides exchange carrier and broadband services. She serves as the chair of the audit committee and also on the compensation committee of the company.

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Ms. Rahe is involved in and serves as a director (or in an equivalent position) of several organizations, including:

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Cincinnati Arts Association (Vice Chair)

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Cincinnati Country Club (Board)

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Cintrifuse (Advisory Board)

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Commonwealth Club (Executive Committee)

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Institutional Real Estate Inc. (Editorial Advisory Board)

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New York Landmark Conservancy (Life Trustee)

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Rush-Presbyterian-St. Luke's Medical Center (Life Trustee)

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Sisters of Notre Dame de Namur (Development Advisory Board)

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The Greater Cincinnati Foundation (Board)

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United Way of Cincinnati (Investment Committee)

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Xavier University Williams College of Business (Board of Executive Advisors)

Ms. Rahe is a recognized leader in the financial services community, both locally and nationally. She brings a seasoned perspective, insight, and financial acumen into issues and strategies relating to the Company's business, including regulatory relationships and enterprise risk management.

16        2019 Proxy Statement    THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR” THE ELECTION OF EACH OF THE NOMINEES.|Proposal 1—Election of Directors

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Our Audit Committee has appointed Crowe Horwath LLP (“Crowe Horwath”("Crowe") as the Company’sCompany's independent registered public accounting firm for the Company’s 2016Company's 2019 fiscal year.

Ernst & Young LLP (“Ernst & Young”) served as our independent registered public accounting firm for the year ended December 31, 2015. The Audit Committee periodically considers whether there should be a rotation of the independent registered public accounting firm. As part of that consideration, during 2015, the Audit Committee conducted a competitive selection process to determine the Company’s independent registered public accounting firm. As a result of that process, the Audit Committee decided to approve the appointment of Crowe Horwath for 2016. We are asking our shareholders to ratify this appointment.

Our Audit Committee is responsible for the appointment, compensation, retention, termination and oversight of the independent registered public accounting firm. The Audit Committee is also responsible for the negotiation of audit fees payable to Crowe Horwath.

Crowe. While the Audit Committee is not required to take any action as a result of the outcome of the vote on this proposal, if shareholders do not ratify the appointment, the Audit Committee will consider whether or not to retain Crowe Horwath in the future. Even if the appointment is ratified, our Audit Committee, at its discretion, may change the appointment at any time if it determines that doing so would be in the best interests of the Company and its shareholders.

Representatives of Crowe are anticipated to attend the Annual Meeting and will be available for questions from shareholders who have submitted their questions electronically prior to the Annual Meeting. No formal statement by representatives of Crowe Horwath or Ernst & Young is anticipated at the Annual Meeting. However, representatives of Crowe Horwath are expected to attend the Annual Meeting to respond to appropriate questions.

Accounting Firm Fees

The following table sets forth the aggregate fees billed for audit services, as well as fees billed with respect to audit-related, tax and all other services, provided by Ernst & YoungCrowe to the Company and its related entities for the last two fiscal years. Any engagement of the Company’sCompany's independent registered public accounting firm for permissible audit, audit-related, tax and other services are preapproved by the Audit Committee. The Audit Committee may provide a general preapproval for a particular type of service or require specific preapproval.

Description of Services:

Audit Fees consist of fees billed for professional services rendered in connection with the audit of our annual consolidated financial statements, HUD audit services performed in connection with the merger with MainSource Financial Group including services related to the Form 8-k of MainSource and internal control over financial reporting, review of consolidated financial statements included in Form 10-Qs, review of certain periodic reports and other documentsFirst Financial filed with the SEC, and services that are normally provided in connection with statutory or regulatory filings or engagements.

Audit-Related Fees in 2018 consist of fees billed for assurance and related services that are reasonably related to the performance of the audit or review of financial statements, including employee benefit plan audits, due diligence services in connection with mergers and acquisitions, services performed in connection with the issuance of subordinated debt offerings and attestation or audit services that are not required by statute or regulation.audits.

Tax Fees consist of fees for professional services for tax preparation and services related to REIT testing procedures, compliance, tax planning, and tax advice such as advice related to mergers and acquisitions and employee benefit plans.consultation.

All Other Fees in 2018 include fees related to information technology attackregulatory compliance audit services and penetration assessments and assessments relating to the design and operating effectiveness of internal controls.out-of-pocket expenses.

2019 Proxy Statement    |Proposal 2—Ratify the Appointment of Crowe Horwath LLP as the Company’s independent registered public accounting firmour Independent Registered Public Accounting Firm for the fiscal year ending December 31, 2016.2019        17

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Report of the Audit Committee

In accordance with its written charter, the Audit Committee oversees the Company’sCompany's financial reporting process on behalf of the Board. Management has the primary responsibility for the financial statements and the reporting process, including the systems of internal controls. The Company’sCompany's independent registered public accounting firm is responsible for expressing an opinion on the conformity of the Company’sCompany's audited financial statements to generally accepted accounting principles and on the Company’sCompany's internal control over financial reporting. In this context, the Audit Committee has reviewed and discussed with management and Ernst & YoungCrowe the audited financial statements for the year ended December 31, 20152018 and Ernst & Young’sCrowe's evaluation of the Company’sCompany's internal control over financial reporting. The Audit Committee has discussed with Ernst & YoungCrowe the matters that are required to be discussed by Auditing Standards No. 16 (Communications with Audit Committees) as amended and adopted by the Public Company Accounting Oversight Board (“PCAOB”("PCAOB") in Rule 3200T.

Ernst & YoungCrowe has provided to the Audit Committee the written disclosures and the letter required by applicable requirements of the PCAOB regarding the independent accountant’saccountant's communications with the Audit Committee concerning independence, and the Audit Committee has discussed with Ernst & YoungCrowe that firm’sfirm's independence. The Audit Committee has concluded that Ernst & Young’sCrowe's provision of audit and non-audit services to First Financial and its affiliates is compatible with Ernst & Young’sCrowe's independence.

The Audit Committee discussed with the Company’sCompany's internal auditors and Ernst & YoungCrowe the overall scope and plans for their respective audits. The Audit Committee met with the internal auditors and with Ernst & Young,Crowe, with and without management present, to discuss the results of their examinations, their evaluations of the Company’sCompany's internal controls, and the overall quality of the Company’sCompany's financial reporting.

In reliance on the reviews and discussions referred to above, the Audit Committee, on February 22, 2019, recommended to the Board, and the Board has approved, that the audited financial statements be included in the Annual Report on Form 10-K for the year ended December 31, 2015,2018, for filing with the SEC.

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WeAs required pursuant to Section 14A of the Securities and Exchange Act of 1934, we are asking our shareholders to approve, on a (non-binding) advisory basis, the compensation of the Company’sCompany's named executive officers (“("named executive officers“officers" or “NEOs”"NEOs") identified in the Summary Compensation Table included in the Executive Compensation portion of this proxy statement beginning at page 27.33. While this vote is advisory, and not binding on our Company, it will provide information to us regarding shareholder sentiment about our compensation principles and objectives and may be considered in future executive compensation related decisions. As determined by our shareholders at the 2011 Annual Meeting of Shareholders, and reconfirmed at the 2017 Annual Meeting of Shareholders, we request this advisory approval each year.

We strongly encourage you to review the Executive Compensation - Compensation—Compensation Discussion and Analysis section of this proxy statement as well as the Summary Compensation Table and other related compensation tables for detailed information about the compensation of our NEOs when making your voting decision on this proposal.

We believe our compensation program has contributed to our Company’sCompany's recent and long-term successes. Our compensation philosophy is based on the following guiding principles and that our executive compensation programs:

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Drive alignment between Company strategy, executive pay, and shareholder value creation;



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Drive alignment between an executive's performance and the interests of shareholders by tying compensation to our Company's performance, also known as "Pay for Performance;"



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Attract, motivate, and retain key talent to deliver consistent, long-term performance; and



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Incorporate proper governance practices to prevent or mitigate inappropriate risk-taking.

We believe information provided in the Executive Compensation portion of this proxy statement demonstrates that our executive compensation program has been designed appropriately to ensure our management’smanagement's interests are aligned with our shareholders’shareholders' interest to support long-term value creation and to differentiate pay based on our performance within our peer group.

Your vote is requested on the following resolution:

RESOLVED, that the shareholders of First Financial Bancorp approve, on an advisory basis, the compensation of the Company’sCompany's named executive officers disclosed in the Compensation Discussion and Analysis, the Summary Compensation Table and the related compensation tables, notes and narrative in the proxy statement for the Company’s 2016Company's 2019 Annual Meeting of Shareholders.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE APPROVAL OF THE ADVISORY RESOLUTION ON EXECUTIVE COMPENSATION.

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A beneficial owner of shares is a person who has sole or shared voting power, meaning the power to control voting decisions, or sole or shared investment power, meaning the power to cause a sale or other disposition of the shares. A person is also considered the beneficial owner of shares to which that person has the right to acquire beneficial ownership within 60 days. For this reason, the following table includes stock options that are exercisable share options and restricted shares that wouldwill become exercisable or vest within 60 days.

¹ NoneThe table below identifies all persons known to us to own beneficially more than 5% of our outstanding common shares as of the 66,609 options listed above haverecord date for the Annual Meeting (April 1, 2019).

The following table shows the closing pricenumber of shares of First Financial common stock on March 30, 2016, which was $18.32 per share.beneficially owned, as of April 1, 2019, by each director and named executive officer of the Company, and all named executive officers and directors of the Company as a group.

²