Form of Incentive Agreement for Performance Unit Award under the Origin Bancorp, Inc. 2012 Stock Incentive Plan, dated December 13, 2022, by and between Origin Bancorp, Inc. and Drake Mills

This Incentive Agreement for Performance Unit Award (the “Agreement”) is made this December 13, 2022 (the “Date of Grant”) by and between Origin Bancorp, Inc. (the “Company”) and Drake Mills (the “Grantee”) pursuant to the Origin Bancorp, Inc. 2012 Stock Incentive Plan, as amended and restated effective January 1, 2017 (the “Plan”).

WHEREAS, Grantee is employed by the Company in the position of President and Chief Executive Officer; and

WHEREAS, in order to incentivize Grantee to exert substantial efforts to maximize the success of the Company, the Board of Directors desires to grant an award to the Grantee under the Plan upon the conditions and terms contained within this Agreement (the “Award”).

NOW, THEREFORE, the Company and Grantee agree as follows:

1.1Grant of Performance Units. The Company hereby grants to Grantee a target number of 129,735 Performance Units (the “Target Number of Performance Units), subject to the terms and conditions provided in this Agreement. Each Performance Unit shall represent a right for the Grantee to receive one (1) share of Stock or cash equal to the Fair Market Value thereof, as determined by the Committee, in its sole discretion, as of the applicable Vesting Date. The “Performance Period” shall mean the period during which the performance criteria and conditions described on Exhibit B (the “Performance Criteria”) will be measured.

1.2Issue Price. The Grantee shall not be required to pay any issue price to the Company in exchange for the Performance Units granted hereunder or, as applicable, upon the issuance of shares of Stock hereunder.

(a)All dividends and other distributions with respect to shares of Stock attributable to the Award that become payable during the Performance Period will accrue when declared and will be paid to the Grantee, in cash, only upon the settlement of the related Performance Units in accordance with the provisions of Section 1.4 below.

(b)The Grantee shall not be entitled to vote shares of Stock attributable to the Award prior to the date(s) on which the Grantee becomes a shareholder of record for such shares of Stock.

(a)The Performance Units, to the extent vested, will be settled as soon as practicable following the applicable Vesting Date, but no later than the last day of the calendar year that includes the

applicable Vesting Date. Upon settlement, the Company shall deliver to the Grantee shares of Stock equal to the number of vested Performance Units or cash equal to the Fair Market Value of such shares, or a combination thereof, as determined by the Company in its sole and absolute discretion. The date that the shares and/or cash are delivered shall be the “Settlement Date” of the vested Performance Units. No fractional Shares shall be issued to Grantee.

(b)To the extent shares of Stock are issued in settlement of this Award, such shares shall be registered in the name of the Grantee and shall be held by Transfer Agent of the Company in an unrestricted shareholder account. The Company shall direct the Transfer Agent to provide a shareholder statement to the Grantee evidencing outright ownership to the Grantee (or the Grantee’s beneficiary in the event of the Grantee’s death, designated as provided in Section 4.8).

1.5Vesting. The Performance Units shall vest as set forth in Exhibit B hereto.

1.6Forfeiture of Award. In addition to events of forfeiture described in Article III, in the event of Grantee’s Termination of Employment prior to the Vesting Date for any reason other than as set forth in Exhibit B, this Award shall be forfeited in its entirety. Upon forfeiture, all rights of the Grantee and obligations of the Company hereunder shall be immediately terminated.

If the Company is not the surviving corporation following a Change in Control, and the surviving corporation following such Change in Control or the acquiring corporation (such surviving corporation or acquiring corporation is hereinafter referred to as the “Acquiror”) does not assume the outstanding Award granted hereunder or does not substitute equivalent equity awards relating to the securities of such Acquiror or its affiliates for such Performance Units, then the Award shall become immediately and fully vested on the date of such Change in Control with respect to 100% of the Target Number of Performance Units. In addition, the Board of Directors or its designee may, in its sole discretion, provide for a cash payment to be made to the Grantee for the outstanding Award upon the consummation of the Change in Control, determined on the basis of the Fair Market Value that would be received in such Change in Control by the holders of the Company's securities relating to such shares of Stock.

If the Company is the surviving corporation following a Change in Control, or the Acquiror assumes the outstanding Award granted hereunder or substitutes equivalent equity awards relating to the securities of such Acquiror or its affiliates for such Performance Units, then the Award or such substitutes therefore shall remain outstanding and be governed by their respective terms and the provisions of the Plan, provided, however, that such Award shall, subject to Section 1.6 hereof, become immediately and fully vested on the Vesting Date with respect to 100% of the Target Number of Performance Units without regard to the performance of the Company or the Acquirer following the Change in Control. Notwithstanding the foregoing, if Participant’s Performance Units are assumed or substituted in connection with a Change in Control, the Target Number of Performance Units will become immediately 100% vested in the event of a termination without Cause within twelve (12) months following the Change in Control.

3.1Confidentiality. The Grantee understands and acknowledges that (i) during the Grantee’s employment with the Company or any Affiliate thereof, the Grantee will have access to Confidential Information of the Company and its Affiliates; (ii) such Confidential Information and the ability of the Company and its Affiliates to reserve such Confidential Information for

their respective and exclusive knowledge and use is of great competitive importance and commercial value to the Company and its Affiliates; (iii) the Company has taken and will continue to take actions to protect the Confidential Information; and (iv) the provisions of this Section are reasonable and necessary to prevent the improper use or disclosure of such Confidential Information. Accordingly, the Grantee agrees that during the term of the Grantee’s employment with the Company or any Affiliate thereof and, following the termination of such employment, until such time as the Confidential Information becomes generally available to the public through no fault of the Grantee or other person under a duty of confidentiality to the Company thereof, the Grantee will not, except as required by law or legal process, in any capacity, use or disclose, or cause to be used or disclosed, any Confidential Information the Grantee acquired while employed by the Company or any Affiliate thereof. For purposes of this Agreement, the term “Confidential Information” shall include, without limitation, the identity of customers, personal customer data, strategic plans, sales data and sales strategy, methods, products, procedures, processes, techniques, financial information, vendor and supplier lists, pricing policies, personnel data and other confidential, business, competitive and proprietary information concerning or related to the Company and/or its Affiliates and their respective businesses, operations, financial conditions, results of operations, competitive position and prospects (collectively “Confidential Information”). The parties hereto agree that nothing in this Agreement shall be construed to limit or negate the law of torts or trade secrets where it provides the Company with broader protection than that provided herein.

3.2Return of Company Property. The parties hereto acknowledge that any material (in computerized or written form) that the Grantee obtains in the course of performing the Grantee’s employment duties with the Company or any Affiliate are the sole and exclusive property of the Company, the Grantee agrees to immediately return any and all records, files, computerized data, documents, Confidential Information, or any other property owned or belonging to the Company in the Grantee’s possession or under the Grantee’s control, without any originals or copies being kept by the Grantee or conveyed to any other person, upon the Grantee’s separation from employment or upon the Company’s request.

3.3Non-Competition; Non-Solicitation of Customers/Employees. The Grantee agrees that during Grantee’s employment by the Company or any Affiliate thereof and for a period of one (1) year thereafter, in the case of Section 3.3(i) and (ii), or a period of two (2) years thereafter, in the case of Section 3.3(iii), the Grantee will not directly, or indirectly, on behalf of himself or any other person, entity or enterprise, do any of the following:

(i)     Divert or attempt to divert from the Company or any Affiliate thereof any business by influencing or attempting to influence or soliciting or attempting to solicit any customers of the Company or any Affiliate thereof or any particular customer with whom the Company or any Affiliate thereof had business contacts in the one-year period immediately preceding the Grantee’s termination or with whom the Grantee may have dealt at any time during the Grantee’s employment by the Company or an Affiliate thereof. The provisions of this item (i) shall apply in the parishes and counties listed in the Exhibit “A” attached hereto and made a part hereof, as the same may be amended from time to time. The parties agree that Exhibit A may be amended from time to time by the Company, which amendments shall be presented to the Grantee in writing and shall be deemed accepted by the Grantee if the Grantee remains employed by the Company on the third (3rd) business day following receipt of any such amendment.

(ii)     Without the prior written consent of the Company, recruit, solicit, hire, attempt to hire, or assist any other person to hire any employee of the Company or an Affiliate thereof or any person who was an employee of the Company or any Affiliate during the six (6) months immediately preceding the Grantee’s Termination of Employment.

(iii)     (A) carry on or engage in the business of banking, including, without limitation, originating, underwriting, closing and selling loans, receiving deposits and otherwise engaging in the business of banking (the “Competitive Services”), or (B) own, manage, operate, join, control or participate in the ownership, management, operation or control, of any business, whether in corporate, proprietorship or partnership form or otherwise where such business is engaged in the provision of Competitive Services. The provisions of this item (iii) shall apply in the parishes and counties listed in the Exhibit “A” attached hereto and made a part hereof, as the same may be amended from time to time. The parties agree that Exhibit A may be amended from time to time by the Company, which amendments shall be presented to the Grantee in writing and shall be deemed accepted by the Grantee if the Grantee remains employed by the Company on the third (3rd) business day following receipt of any such amendment.

(iv)      Otherwise assist any person in any way to do, or attempt to do, anything prohibited by the foregoing.

3.4Remedies. Notwithstanding any other provision of this Agreement, if the Company determines that the Grantee has breached or threatened to breach any provision of this Article III, then, upon written notice of the Company and without consideration, any Performance Units whether or not vested shall be immediately forfeited, the shares and cash (including proceeds received upon a sale of the shares) issued to the Participant shall be subject to recoupment and any and all rights to receive any remaining benefits under this Agreement shall be immediately cancelled. In addition, the Company shall be entitled to injunctive and other equitable relief (without the necessity of showing actual monetary damages or of posting any bond or other security): (i) restraining and enjoining any act which would constitute a breach, or (ii) compelling the performance of any obligation which, if not performed, would constitute a breach, as well as any other remedies available to the Company, including monetary damages. Upon the Company’s request, the Grantee shall provide reasonable assurances and evidence of compliance with the restrictive covenants set forth in this Article III. If any court of competent jurisdiction shall deem any provision in this Article III too restrictive, the other provisions shall stand, and the court shall modify the unduly restrictive provision to the point of greatest restriction permissible by law. The restrictive covenants set forth in this Article III shall survive the termination of this Agreement, the forfeiture of the Award, and the Grantee’s Termination of Employment with the Company and all Affiliates for any reason, and the Grantee shall continue to be bound by the terms of this Article III as if this Agreement was still in effect.

4.1Adjustments Upon Changes in Stock. In case of any reorganization, recapitalization, reclassification, stock split, stock dividend, distribution, combination of shares, merger, consolidation, rights offering, or any other changes in the corporate structure or shares of the Company, appropriate adjustments may be made by the Committee or the Board of Directors, as the case may be, (or if the Company is not the surviving corporation in any such transaction, the board of directors of the surviving corporation) in the aggregate number and kind of shares subject to the Plan, and the number and kind of shares subject to this Award. Appropriate adjustments may also be made by the Committee or the Board of Directors, as the case may be, in the terms of any Awards under the Plan, subject to the provisions of the Plan, to reflect such changes and to modify any other terms of outstanding Awards on an equitable basis. Any such adjustments made by the Committee or the Board of Directors Performance pursuant to this Section shall be conclusive and binding for all purposes under the Plan.

(a)The Board of Directors may suspend or terminate the Plan or any portion thereof at any time, and, subject to limitations contained therein and, subject to shareholder approval if required, may amend the Plan from time to time in such respects as the Board of Directors may deem advisable in order that any awards thereunder shall conform to any change in applicable laws or regulations or in any other respect the Board of Directors may deem to be in the best interests of the Company; provided, however, that no such amendment, suspension, or termination shall adversely alter or impair the Award granted hereunder without the consent of the Grantee.

(b)The Committee may amend or modify the Award granted hereunder in any manner to the extent that the Committee would have had the authority under the Plan initially to grant the Award as so modified or amended; however, no such amendment or modification shall adversely alter or impair the Award granted hereunder without the consent of the Grantee.

(c)Notwithstanding the foregoing, the Plan and the Agreement may be amended without any additional consideration to the Grantee to the extent necessary to comply with, or avoid penalties under, Section 409A of the Code, even if those amendments reduce, restrict or eliminate rights granted prior to such amendments.

4.3No Right To Employment/Other Service. None of the actions of the Company in establishing the Plan, the actions taken by the Company, the Board of Directors or the Committee under the Plan, or the granting of the Award pursuant to this Agreement shall be deemed (a) to create any obligation on the part of the Company or any Affiliate or on the Board of Directors of the Company or such Affiliate to retain the Grantee as an employee, consultant, director or other service provider or to nominate Grantee for election to the Board of Directors, or (b) to be evidence of any agreement or understanding, express or implied, that the person has a right to continue as an employee, consultant, other service provider, or non-employee director for any period of time or at any particular rate of compensation.

4.4Plan and Grant Document Control. The grant of the Award hereunder is governed and controlled by the terms of the Plan and this Agreement. All the provisions of the Plan, as such may be amended from time to time, are hereby incorporated into this Agreement by this reference. All capitalized terms utilized in this Agreement shall have the same meaning as in the Plan, except as otherwise specifically provided herein.

4.5Governing Law. All matters relating to the Plan or to awards granted under the Plan pursuant to this Agreement shall be governed by and construed in accordance with the laws of the State of Louisiana without regard to the principles of conflict of laws.

4.6Trust Arrangement. All benefits under the Plan represent an unsecured promise to pay by the Company. The Plan shall be unfunded and the benefits hereunder shall be paid only from the general assets of the Company resulting in the Grantee having no greater rights than the Company's general creditors; provided, however, nothing herein shall prevent or prohibit the Company from establishing a trust or other arrangement for the purpose of providing for the payment of the benefits payable under the Plan.

4.7No Impact on Benefits. The Award granted hereunder is not compensation for purposes of calculating the Grantee’s rights under any employee benefit plan of the Company or any Affiliate that does not specifically require the inclusion of Awards in calculating benefits.

4.8Beneficiary Designation. The Grantee may name a beneficiary or beneficiaries to receive any vested portion of the Award that is unpaid at the Grantee’s death. Unless otherwise provided in the beneficiary designation, each designation will revoke all prior designations made by the Grantee, must be made in such manner as prescribed by the Committee and will be effective only when received by the Committee (or its authorized delegate). If the Grantee has not made an effective beneficiary designation, the deceased Grantee’s beneficiary will be the Grantee’s surviving spouse or, if none, the deceased Grantee’s estate. The identity of a Grantee’s designated beneficiary will be based only on the information included in the latest beneficiary designation received by the Committee (or its authorized delegated) and will not be inferred from any other evidence.

4.9Taxes. The Company shall have the power and the right to deduct or withhold, or require the Grantee to remit to the Company, the minimum statutory amount to satisfy federal, state and local taxes required by law or regulation to be withheld with respect to any taxable event arising as a result of the Award granted hereunder, if any. No delivery of shares or cash shall be made unless and until appropriate arrangements for the payment of such taxes have been made. With respect to withholding required upon any taxable event arising as a result of the Award granted hereunder, the Grantee may elect, subject to the approval of the Committee, to satisfy the withholding requirement, in whole or in part, by having the Company withhold shares of Stock of the Company having a Fair Market Value on the date the tax is to be determined equal to the minimum statutory total tax that could be imposed on the transaction. Alternatively, the Grantee may elect for such taxes to be withheld from other compensation otherwise due to the Grantee from the Company and provided Grantee’s other compensation is sufficient to cover such taxes. All such elections shall be irrevocable, made in writing and signed by the Grantee, and shall be subject to any restrictions or limitations that the Committee, in its sole discretion, deems appropriate. All such elections shall be made and filed with the Committee in the manner determined by the Committee on or before the applicable Vesting Date, or such earlier date as shall be determined by the Committee. If an election has not been made by the Grantee, or the amount of the taxes required to be withheld has not been remitted by the Grantee to the Company on or before the applicable Vesting Date, the Grantee hereby authorizes the Company to withhold from amounts payable under the Award cash or shares of Stock of the Company having a Fair Market Value equal to the tax required to be withheld.

4.10 Gender and Number. Except where otherwise indicated by the context, any masculine term used herein also shall include the feminine, the plural shall include the singular, and the singular shall include the plural.

4.11 Severability. In the event any provision of the Plan or this Agreement shall be held illegal or invalid for any reason, the illegality or invalidity shall not affect the remaining parts of the Plan or this Agreement, and the Plan or this Agreement shall be construed and enforced as if the illegal or invalid provision had not been included.

4.12 Transfer Restrictions. The Performance Units issued to the Grantee hereunder may not be sold, transferred by gift, pledged, hypothecated, or otherwise transferred or disposed of by the

Grantee prior to the Settlement Date. Any attempt to transfer any Performance Units in violation of this Section 4.10 shall be null and void and shall be disregarded. The terms of this Agreement and the Plan shall be binding upon the executors, administrators, heirs, successors and assigns of the Grantee.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed to be effective as of the date first noted above.

Bienville Parish, Louisiana

Claiborne Parish, Louisiana

Jackson Parish, Louisiana

Lincoln Parish, Louisiana

Morehouse Parish, Louisiana

Ouachita Parish, Louisiana

Union Parish, Louisiana

Hinds Country, Mississippi

Lafayette County, Mississippi

Madison County, Mississippi

Collin County, Texas

Dallas County, Texas

Harris County, Texas

Montgomery County, Texas

Tarrant County, Texas

Smith County, Texas

Panola County, Texas

Rusk County, Texas

1.    Except as otherwise provided in the Agreement, the Performance Units shall be eligible to vest as follows:

(i)20% of the Performance Units (“Tranche 1 Performance Units”) will be eligible to vest on the later of the 2025 Vesting Date or the Tranche 1 Hurdle Achievement Date, provided that Grantee remains continuously employed by the Company on such date.

(ii)20% of the Performance Units (“Tranche 2 Performance Units”) will be eligible to vest on the later of the 2026 Vesting Date or the Tranche 2 Hurdle Achievement Date, provided that Grantee remains continuously employed by the Company on such date.

(iii)20% of the Performance Units (“Tranche 3 Performance Units”) will be eligible to vest on the later of the 2027 Vesting Date or the Tranche 3 Hurdle Achievement Date, provided that Grantee remains continuously employed by the Company on such date.

(iv)20% of the Performance Units (“Tranche 4 Performance Units”) will be eligible to vest on the later of the 2028 Vesting Date or the Tranche 4 Hurdle Achievement Date, provided that Grantee remains continuously employed by the Company on such date.

(v)20% of the Performance Units (“Tranche 5 Performance Units”) will be eligible to vest on the later of the 2029 Vesting Date or the Tranche 5 Hurdle Achievement Date, provided that Grantee remains continuously employed by the Company on such date.

2.    Subject to Section 1.6 and Article III of the Agreement, Grantee shall vest in the Performance Units on the earliest of (a) the applicable Vesting Date, provided the Grantee remains employed by the Company or an Affiliate through that date, (b) the Grantee’s death, or (c) the Grantee’s Disability. If the Grantee has a Qualified Termination during the Performance Period, then the Performance Units shall remain outstanding and eligible to vest based on achievement of the Stock Price Hurdles during the Performance Period. For the avoidance of doubt, the Performance Units shall only be earned if the applicable Stock Price Hurdles are achieved during the Performance Period as described in this Exhibit B. If the Stock Price Hurdles are not achieved as described in this Exhibit B, then the Performance Units shall not vest. In the event that any Performance Units fail to vest during the Performance Period, such unvested Performance Units will be forfeited as of the last day of the Performance Period without consideration payable by the Company and the Grantee will have no further rights with respect thereto.

“Hurdle Achievement” means, with respect to any applicable Tranche, the occurrence of (i) the closing price per Share, as reported on the Nasdaq Global Select Market, during any twenty (20) consecutive trading day period during the Performance Period exceeding (ii) the Stock Price Hurdle applicable to such Tranche. For the avoidance of doubt, Hurdle Achievement for any Tranche must

occur during the Performance Period, and any trading days outside of the Performance Period will not be taken into account for purposes of determining whether Hurdle Achievement for any Tranche has occurred. In the event the Shares are not listed on the Nasdaq Global Select Market as of any relevant date of determination during the Performance Period, then any reference in this Agreement to the Nasdaq Global Select Market will be deemed to refer to the principal securities exchange or market on which the Shares are traded or quoted.

“Performance Period” means the period beginning on December 13, 2022 and concluding on December 13, 2029.

“Qualified Termination” means the Grantee’s Termination of Employment by the Company without “Cause” or by Grantee for “Good Reason” (as such terms are defined in Grantee’s Restated Employment Agreement with the Company, dated as of February 27, 2020.

“Stock Price Hurdle” means the price per Share set forth in the table below; provided that the Stock Price Hurdles set forth in the table must be maintained for twenty (20) consecutive trading days in order for such Stock Price Hurdle to be achieved. The Stock Price Hurdle shall be equitably adjusted by the Committee in order to prevent the dilution or enlargement of benefits intended to be provided under this Award Agreement in the event of certain changes in the Company’s corporate structure or the occurrence of other events that affect Shares, as contemplated by the Plan.

“Tranche 1 Hurdle Achievement Date” means the date that the Committee determines and certifies achievement of the Tranche 1 Stock Price Hurdle.

“Tranche 2 Hurdle Achievement Date” means the date that the Committee determines and certifies achievement of the Tranche 2 Stock Price Hurdle.

“Tranche 3 Hurdle Achievement Date” means the date that the Committee determines and certifies achievement of the Tranche 3 Stock Price Hurdle.

“Tranche 4 Hurdle Achievement Date” means the date that the Committee determines and certifies achievement of the Tranche 4 Stock Price Hurdle.

“Tranche 5 Hurdle Achievement Date” means the date that the Committee determines and certifies achievement of the Tranche 5 Stock Price Hurdle.

“Vesting Date” means the Tranche 1 Hurdle Achievement Date, Tranche 2 Hurdle Achievement Date, Tranche 3 Hurdle Achievement Date, Tranche 4 Hurdle Achievement Date, Tranche 5 Hurdle Achievement Date, the 2025 Vesting Date, 2026 Vesting Date, 2027 Vesting Date, the 2028 Vesting Date and the 2029 Vesting Date, as applicable.

“2025 Vesting Date” means December 13, 2025.

“2027 Vesting Date” means December 13, 2027.

“2028 Vesting Date” means December 13, 2028.

“2029 Vesting Date” means December 13, 2029.