a06_30x2022obnkinvestorp

ORIGIN BANCORP, INC. _______ 2Q TWENTY22 INVESTOR PRESENTATION ORIGIN BANCORP, INC.

ORIGIN BANCORP, INC. _______ This presentation contains certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include information regarding Origin Bancorp, Inc.'s ("Origin" or the "Company") future financial performance, business and growth strategy, projected plans and objectives, including the Company's loan loss reserves and allowance for credit losses related to the COVID-19 pandemic and any expected purchases of its outstanding common stock, and related transactions and other projections based on macroeconomic and industry trends, including expectations regarding and efforts to respond to the COVID-19 pandemic and changes to interest rates by the Federal Reserve and the resulting impact on Origin's results of operations, estimated forbearance amounts and expectations regarding the Company's liquidity, including in connection with advances obtained from the FHLB, which are all subject to change and may be inherently unreliable due to the multiple factors that impact broader economic and industry trends, and any such changes may be material. Such forward-looking statements are based on various facts and derived utilizing important assumptions and current expectations, estimates and projections about Origin and its subsidiaries, any of which may change over time and some of which may be beyond Origin's control. Statements or statistics preceded by, followed by or that otherwise include the words "assumes," "anticipates," "believes," "estimates," "expects," “foresees,” "intends," "plans," "projects," and similar expressions or future or conditional verbs such as "could," "may," “might,” "should," "will," and "would" and variations of such terms are generally forward-looking in nature and not historical facts, although not all forward-looking statements include the foregoing words. Further, certain factors that could affect the Company's future results and cause actual results to differ materially from those expressed in the forward-looking statements include, but are not limited to: deterioration of Origin's asset quality; factors that can impact the performance of Origin's loan portfolio, including real estate values and liquidity in Origin's primary market areas; the financial health of Origin's commercial borrowers and the success of construction projects that Origin finances; changes in the value of collateral securing Origin's loans; Origin's ability to anticipate interest rate changes and manage interest rate risk (including the impact of higher interest rates on macroeconomic conditions, and customer and client behavior); the effectiveness of Origin's risk management framework and quantitative models; the risk of widespread inflation; Origin's inability to receive dividends from Origin Bank and to service debt, pay dividends to Origin's common stockholders, repurchase Origin's shares of common stock and satisfy obligations as they become due; business and economic conditions generally and in the financial services industry, nationally and within Origin's primary market areas, including the impact of supply-chain disruptions and labor pressures; changes in Origin's operation or expansion strategy or Origin's ability to prudently manage its growth and execute its strategy; changes in management personnel; Origin's ability to maintain important customer relationships, reputation or otherwise avoid liquidity risks; increasing costs as Origin grows deposits; operational risks associated with Origin's business; volatility and direction of market interest rates; increased competition in the financial services industry, particularly from regional and national institutions; difficult market conditions and unfavorable economic trends in the United States generally, and particularly in the market areas in which Origin operates and in which its loans are concentrated; an increase in unemployment levels and slowdowns in economic growth; Origin's level of nonperforming assets and the costs associated with resolving any problem loans including litigation and other costs; the credit risk associated with the substantial amount of commercial real estate, construction and land development, and commercial loans in Origin's loan portfolio; changes in laws, rules, regulations, interpretations or policies relating to financial institutions, and potential expenses associated with complying with such regulations; periodic changes to the extensive body of accounting rules and best practices; further government intervention in the U.S. financial system; compliance with governmental and regulatory requirements, including the Dodd-Frank Wall Street Reform and Consumer Protection Act and others relating to banking, consumer protection, securities, and tax matters; Origin's ability to comply with applicable capital and liquidity requirements, including its ability to generate liquidity internally or raise capital on favorable terms, including continued access to the debt and equity capital markets; changes in the utility of Origin's non-GAAP liquidity measurements and its underlying assumptions or estimates; uncertainty regarding the transition away from the London Interbank Offered Rate ("LIBOR") and the impact of any replacement alternatives such as the Secured Overnight Financing Rate ("SOFR") on Origin's business; possible changes in trade, monetary, and fiscal policies, laws, and regulations and other activities of governments, agencies and similar organizations; natural disasters and adverse weather events, acts of terrorism, an outbreak of hostilities (including the impacts related to or resulting from Russia's military action in Ukraine, including the imposition of additional sanctions and export controls, as well as the broader impacts to financial markets and the global macroeconomic and geopolitical environments), regional or national protests and civil unrest (including any resulting branch closures or property damage), widespread illness or public health outbreaks or other international or domestic calamities, and other matters beyond Origin's control; and system failures, cybersecurity threats and/or security breaches and the cost of defending against them. For a discussion of these and other risks that may cause actual results to differ from expectations, please refer to the sections titled "Cautionary Note Regarding Forward-Looking Statements" and "Risk Factors" in Origin's most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") and any updates to those sections set forth in Origin's subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. If one or more events related to these or other risks or uncertainties materialize, or if Origin's underlying assumptions prove to be incorrect, actual results may differ materially from what Origin anticipates. Accordingly, you should not place undue reliance on any forward-looking statements. Any forward-looking statement speaks only as of the date on which it is made, and Origin does not undertake any obligation to publicly update or review any forward-looking statement, whether as a result of new information, future developments, or otherwise. The risks relating to the proposed BTH merger include, without limitation, the timing to consummate the proposed merger; the risk that a condition to the closing of the proposed merger may not be satisfied; the parties' ability to achieve the synergies and value creation contemplated by the proposed merger; the parties' ability to promptly and effectively integrate the businesses of Origin and BTH, including unexpected transaction costs, the costs of integrating operations, severance, professional fees and other expenses; the diversion of management time on issues related to the merger; the failure to consummate or any delay in consummating the merger for other reasons; changes in laws or regulations; the risks of customer and employee loss and business disruption, including, without limitation, as the result of difficulties in maintaining relationships with employees; increased competitive pressures and solicitations of customers and employees by competitors; and the difficulties and risks inherent with entering new markets. New risks and uncertainties arise from time to time, and it is not possible for Origin to predict those events or how they may affect Origin. In addition, Origin cannot assess the impact of each factor on Origin's business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Furthermore, many of these risks and uncertainties are currently amplified by, may continue to be amplified by, or may, in the future, be amplified by the COVID-19 pandemic and the impact of varying governmental responses that affect Origin's customers and the economies where they operate. All forward-looking statements, expressed or implied, included in this communication are expressly qualified in their entirety by this cautionary statement. This cautionary statement should also be considered in connection with any subsequent written or oral forward-looking statements that Origin or persons acting on Origin's behalf may issue. Annualized, pro forma, adjusted projected and estimated numbers are used for illustrative purposes only, are not forecasts, and may not reflect actual results. Certain prior period amounts have been reclassified to conform to the current year financial statement presentations. These reclassifications did not impact previously reported net income or comprehensive income. Origin reports its results in accordance with United States generally accepted accounting principles ("GAAP"). However, management believes that certain supplemental non-GAAP financial measures used in managing its business may provide meaningful information to investors about underlying trends in its business. Management uses these non-GAAP measures to evaluate the Company's operating performance and believes that these non-GAAP measures provide information that is important to investors and that is useful in understanding Origin's results of operations. However, non-GAAP financial measures are supplemental and should be viewed in addition to, and not as an alternative for, Origin's reported results prepared in accordance with GAAP. The following are the non-GAAP measures used in this presentation: • Tangible common equity is defined as total common stockholders' equity less goodwill and other intangible assets, net. • Tangible book value per common share is determined by dividing tangible common equity by common shares outstanding at the end of the period. • Pre-tax, pre-provision earnings is calculated by adding provision for credit losses and income tax expense to net income. • Pre-tax, pre-provision return on average assets is calculated by dividing pre-tax, pre-provision earnings by number of days in the quarter, multiplying by the number of days in the year, then dividing by total average assets. • Pre-tax, pre-provision return on average stockholder's equity is calculated by dividing pre-tax, pre-provision earnings by number of days in the quarter, multiplying by the number of days in the year, then dividing by total average stockholder's equity. • Core deposits is calculated by subtracting brokered deposits and time deposits greater than $250,000 from total deposits. • Adjusted efficiency ratio is calculated by dividing the remainder of total noninterest expense less mortgage banking and insurance expense by the sum of net interest income plus the remainder of noninterest income less mortgage banking and insurance income. See slides 20-23 in this presentation for a reconciliation between the non-GAAP measures used in this presentation and their comparable GAAP numbers. 2 FORWARD-LOOKING STATEMENTS AND NON-GAAP MEASURES

ORIGIN BANCORP, INC. _______ 9 11 19 6 TEXAS Entry: DFW 2008 | Houston 2013 Loans: $3,005 Deposits: $2,798 LOUISIANA Entry: 1912 Loans: $1,397 Deposits: $2,902 DOLLARS IN MILLIONS, UNAUDITED (1) (2) 3 ORIGIN COMPANY SNAPSHOT • Origin Bancorp, Inc., the holding company for Origin Bank, is headquartered in Ruston, LA • Origin Bank was founded in 1912 • 45 banking centers operating across Texas, Louisiana & Mississippi DEPOSITS & LOANS BY STATE Note: All financial information is as of 6/30/22. (1) Non-market based deposits are not included in state deposits. (2) Excludes mortgage warehouse loans. MISSISSIPPI Entry: 2010 Loans: $594 Deposits: $603 10% 12% 46% 28% 44% 60% Loans (2)Deposits (1) ICS ICS

ORIGIN BANCORP, INC. _______ 4 A UNIQUE & DEFINED CULTURE

ORIGIN BANCORP, INC. _______ QTD YTD Balance Sheet 2Q22 1Q22 Linked Qtr % Δ 2Q21 YoY % Δ 2Q22 2Q21 YoY % Δ Total Loans Held for Investment ("LHFI") $ 5,528,093 $ 5,194,406 6.4 % $ 5,396,306 2.4 % $ 5,528,093 $ 5,396,306 2.4 % Total Assets 8,111,524 8,112,295 — 7,268,068 11.6 8,111,524 7,268,068 11.6 Total Deposits 6,303,158 6,767,179 (6.9) 6,028,352 4.6 6,303,158 6,028,352 4.6 Tangible Book Value per Common Share(1)(2) 25.05 26.37 (5.0) 28.01 (10.6) 25.05 28.01 (10.6) Income Statement Net Interest Income $ 59,504 $ 52,502 13.3 % $ 54,292 9.6 % $ 112,006 $ 109,531 2.3 % Noninterest Income 14,216 15,906 (10.6) 12,438 14.3 30,122 29,569 1.9 Noninterest Expense 44,150 42,774 3.2 37,832 16.7 86,924 77,268 12.5 Net Income 21,311 20,683 3.0 27,733 (23.2) 41,994 53,246 (21.1) Pre-Tax, Pre-Provision Earnings ("PTPP")(1) 29,570 25,634 15.4 28,898 2.3 55,204 61,832 (10.7) Diluted EPS 0.90 0.87 3.4 1.17 (23.1) 1.77 2.26 (21.7) Dividends Declared per Common Share 0.15 0.13 15.4 0.13 15.4 0.28 0.23 21.7 Selected Ratios NIM - FTE 3.23 % 2.86 % 12.9 % 3.12 % 3.5 % 3.04 % 3.17 % (4.1) % Efficiency Ratio 59.89 62.53 (4.2) 56.69 5.6 61.16 55.55 10.1 Adjusted Efficiency Ratio(2) 55.35 59.93 (7.6) 51.50 7.5 57.50 51.28 12.1 ROAA (annualized) 1.08 1.04 3.8 1.49 (27.5) 1.06 1.45 (26.9) ROAE (annualized) 12.81 11.61 10.3 16.54 (22.6) 12.19 16.14 (24.5) PTPP ROAA (annualized)(1) 1.49 1.29 15.5 1.55 (3.9) 1.39 1.68 (17.3) PTPP ROAE (annualized)(1) 17.77 14.39 23.5 17.23 3.1 16.02 18.74 (14.5) Total Nonperforming Assets to Total Assets 0.23 0.32 (28.1) 0.51 (54.9) 0.23 0.51 (54.9) Allowance for Loan Credit Losses to Total LHFI 1.14 1.20 (5.0) 1.43 (20.3) 1.14 1.43 (20.3) Net Charge-offs to Total Average LHFI (annualized) 0.12 0.14 (14.3) 0.20 (40.0) 0.13 0.21 (38.1) DOLLARS IN THOUSANDS, EXCEPT PER SHARE AMOUNTS, UNAUDITED 5 (1) A decline of $121.7 million in accumulated other comprehensive loss during the YTD period ended June 30, 2022, negatively impacted total stockholders' equity and tangible common equity and caused tangible book value per common share to decline by $5.11 primarily due to the steepening of the short end of the yield curve that occurred during 2022 and its impact on our investment portfolio, however it did not impact regulatory capital. (2) As used in this presentation, tangible book value per common share, PTPP, adjusted efficiency ratio, PTPP ROAA, and PTPP ROAE are non-GAAP financial measures. For a reconciliation of these non-GAAP financial measures to their comparable GAAP measures, see slides 20-23 of this presentation. PERFORMANCE HIGHLIGHTS - SECOND QUARTER 2022

ORIGIN BANCORP, INC. _______ TRENDING KEY MEASURES 47,785 73,720 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 Total Revenues ($) UNAUDITED Diluted EPS ($)Net Income ($) Total LHFI excluding PPP and MW LOC ($) Total Deposits ($) 0.53 0.90 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 12,702 21,311 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 3,672 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 4,995 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 DOLLARS IN THOUSANDS DOLLARS IN THOUSANDS DOLLARS IN MILLIONS DOLLARS IN MILLIONS Core Deposits ($)(1) 3,117 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 DOLLARS IN MILLIONS (1) As used in this presentation, core deposits is a non-GAAP financial measure. For a reconciliation of non-GAAP financial measures to their comparable GAAP measures, see slides 20-23 of this presentation. 6 3,102 6,1036,303

ORIGIN BANCORP, INC. _______ TRENDING KEY MEASURES CONTINUED Pre-Tax Pre-Provision Earnings ($)(1) Efficiency Ratio (%) 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 UNAUDITED 15,773 29,570 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 Net Charge Offs ($) 121 1,553 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 Net Charge Offs to Total Average LHFI (%)(2) 0.01 0.12 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 DOLLARS IN THOUSANDS DOLLARS IN THOUSANDS Adjusted Efficiency Ratio (%)(1) 60.62 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 21.07 2Q 18 3Q 18 4Q 18 1Q 19 2Q 19 3Q 19 4Q 19 1Q 20 2Q 20 3Q 20 4Q 20 1Q 21 2Q 21 3Q 21 4Q 21 1Q 22 2Q 22 Tangible Book Value per Common Share ($)(1)(3) (1) As used in this presentation, PTPP, Adjusted efficiency ratio, and tangible book value per common share are non-GAAP financial measures. For a reconciliation of these non- GAAP financial measures to their comparable GAAP measures, see slides 20-23 of this presentation. (2) Annualized. (3) A decline of $121.7 million in accumulated other comprehensive loss during the YTD period ended June 30, 2022, negatively impacted total stockholders' equity and tangible common equity and caused tangible book value per common share to decline by $5.11 primarily due to the steepening of the short end of the yield curve that occurred during 2022 and its impact on our investment portfolio, however it did not impact regulatory capital. 7 66.99 59.89 25.05 55.35

ORIGIN BANCORP, INC. _______ 8 1,741 1,956 2,247 2,620 3,005 1,067 1,127 1,343 1,545 1,711 674 829 904 1,075 1,294 DFW Houston 2018 2019 2020 2021 2Q2022 Deposit Trends by Texas Market ($) (2) Loan Trends by Texas Market ($) (1) TEXAS GROWTH STORY Texas Franchise Highlights DOLLARS IN MILLIONS, UNAUDITED • 20 branches throughout 5 counties in the 4th and 5th largest MSAs in the United States • Texas franchise represents 60% of LHFI, excluding mortgage warehouse loans, and 44% of deposits, excluding non-market-based deposits, at June 30, 2022 1,395 1,854 2,574 3,132 2,798 772 989 1,581 1,925 1,655 623 865 993 1,207 1,143 DFW Houston 2018 2019 2020 2021 2Q2022 CAGR 16.9% CAGR 22.0% (1) Excludes mortgage warehouse loans and, for all periods prior to 2Q2022, PPP loans. (2) Non-market based deposits are not included in state deposits.

ORIGIN BANCORP, INC. _______ ORIGIN BANK + BTH —— ENHANCING —— OUR TEXAS FRANCHISE • Shared cultures and business models focused on relationship banking leading to seamless integration • Compelling footprint expansion along I-20 corridor in East Texas with meaningful overlap in DFW • Significant opportunity for growth in new and existing markets by building and expanding client relationships • ~50% C&I loans, a unique TX opportunity • Financially attractive with double digit earnings accretion and ~2.2 year TBVPS earnback • Pro forma capital ratios remain strong, positioning OBNK for continued, robust organic growth • All regulatory and shareholder approvals received - expected to close 3Q22 9

ORIGIN BANCORP, INC. _______ 10 ORGANIC LOAN GROWTH 3,581 3,869 4,094 4,498 4,995 2018 2019 2020 2021 2Q2022 2,000 3,000 4,000 5,000 LHFI Key Data DOLLARS IN MILLIONS, UNAUDITED IDT 582632 • LHFI, excluding PPP and mortgage warehouse lines of credit, increased 39.5% from 12/31/2018, with a CAGR of 10.0%. Total C&I, excluding PPP, owner occupied CRE and C&D, increased 23.5% from 12/31/2018, with a CAGR of 6.2%. • Total LHFI at 6/30/2022, excluding mortgage warehouse lines of credit and PPP, were $5.00 billion, reflecting a strong $336.3 million, or 29.0% annualized increase, compared to the linked quarter. • Total mortgage warehouse lines of credit were $531.9 million, or 9.6%, of total LHFI at 6/30/2022. LHFI excluding MW LOC and PPP Growth ($) CAGR: 10.0% 1,803 1,902 1,833 2,032 2,226 2018 2019 2020 2021 2Q2022 1,000 2,000 3,000 437 582632 C&I (excluding PPP), Owner Occupied CRE and C&D Growth ($) CAGR: 6.2%

ORIGIN BANCORP, INC. _______ MW LOC: 10% Real Estate & Construction: 8% Finance & Insurance: 6% Transportation Svcs: 4% Commercial Svcs: 2% Retail Dealers: 2% Retail Shopping: 2% Restaurants: 2% Professional Svcs: 1% Consumer Svcs: 1% Banks: 1% Healthcare: 1% Materials&Commodities: 1% Entertainment: 1% Energy: 1%Misc: 7% Commercial & Industrial ("C&I") 26% Owner Occupied Construction/ Land/Land Development ("C&D"): 3% Owner Occupied Commercial Real Estate ("CRE"): 11% MW LOC: 10%Non-Owner Occupied C&D: 8% Non-Owner Occupied CRE: 24% Residential Real Estate & Consumer 18% Office Building: 6% Retail Shopping: 6% Real Estate & Construction: 6% Healthcare: 4% Multi-family: 2% Hotel: 2% Restaurant: 1% Finance & Insurance: 1% Misc: 4% 11 WELL DIVERSIFIED LOAN PORTFOLIO (Dollars in thousands) 2Q22 1Q22 4Q21 3Q21 2Q21 C&I excl. PPP $ 1,429,338 $ 1,326,443 $ 1,348,474 $ 1,218,246 $ 1,200,881 Owner Occupied CRE 609,358 588,279 523,655 473,558 457,895 Owner Occupied C&D 187,249 179,074 160,131 151,650 122,933 MW LOC 531,888 503,249 627,078 713,339 865,255 Total Commercial 2,757,833 2,597,045 2,659,338 2,556,793 2,646,964 Non-Owner Occupied CRE 1,299,696 1,213,103 1,169,857 1,116,961 1,022,641 Non-Owner Occupied C&D 448,307 414,276 369,952 367,270 374,237 Residential Real Estate 1,005,623 922,054 909,739 913,411 966,301 Consumer Loans 15,733 15,774 16,684 15,896 16,253 PPP Loans 901 32,154 105,761 216,957 369,910 Total Loans $ 5,528,093 $ 5,194,406 $ 5,231,331 $ 5,187,288 $ 5,396,306 Loan Portfolio Details Non-Owner Occupied CRE and C&D: (1) $1,748 C&I, Owner Occupied CRE and C&D, MW LOC: (1) $2,758 C&I, Owner Occupied CRE and C&D, MW LOC: 50% Non-Owner Occupied CRE and C&D: 32% (1) Does not include loans held for sale or PPP loans. Loan Composition at 6/30/2022: (1) $5,527 DOLLARS IN MILLIONS, UNAUDITED ILP

ORIGIN BANCORP, INC. _______ 12 3,547 3,658 3,616 3,976 3,767 1,838 1,966 2,111 2,218 2,289 582 562 535 503 6,244 6,206 6,289 6,729 6,559 Interest-bearing Demand Noninterest-bearing Time Deposits Brokered 2Q21 3Q21 4Q21 1Q22 2Q22 Average Deposits ($) DEPOSIT TRENDS 0.78 0.67 0.59 0.54 0.49 0.31 0.30 0.28 0.26 0.29 0.22 0.19 0.07 0.09 0.08 0.12 0.77 Time Deposits Cost of Interest-bearing Deposits Cost of Total Deposits Average Quarterly Fed Funds Rate 2Q21 3Q21 4Q21 1Q22 2Q22 Deposit Cost Trends (QTD Annualized) (%) Time Deposit Repricing Schedule * Maturity Balance ($) WAR (%) 3Q22 159 0.35 4Q22 114 0.37 1Q23 60 0.44 2Q23 61 0.48 3Q23+ 95 0.79 Total 489 0.47 DOLLARS IN MILLIONS, UNAUDITED IDT * Projection is based upon June 30, 2022, time deposit balances. • Average deposit rate decreased 3 basis points from 0.22% in 2Q21 to 0.19% in 2Q22. Average quarterly fed funds rate increased 69 basis points from 0.07% at 2Q21 to 0.77% at 2Q22. • The beta of the cost of total deposits to the quarterly average fed funds rate is 3.0% 2Q22 compared to 1Q22. • Average noninterest-bearing deposits increased $450.9 million compared to the 2Q21 quarter and represented 34.9% of total average deposits. • Overall cost of total deposits has declined 13.6% since 2Q21. • There were $150.1 million in new and renewed CD's during 2Q22 with a weighted average interest rate of 0.20%. 227 632 0.21 0.19 0.17

ORIGIN BANCORP, INC. _______ 1.66 1.52 1.35 1.36 0.94 Classified LHFI / Total LHFI excl. PPP Loans (%) Net Charge-Offs / Average LHFI excl. PPP Loans (annualized) (%) 2Q21 3Q21 4Q21 1Q22 2Q22 0.23 0.24 0.22 0.14 0.12 0.61 0.49 0.49 0.41 0.25 0.61 0.52 0.50 0.42 0.13 Nonperforming LHFI / LHFI excl. PPP loans (%) Past due LHFI / LHFI excl. PPP loans (%) 2Q21 3Q21 4Q21 1Q22 2Q22 13 CREDIT QUALITY Asset Quality Trends (%) Allowance for Loan Credit Losses ("ALCL") 77,104 69,947 64,586 62,173 63,123 1.43 1.35 1.84 1.63 1.43 1.33 1.25 ALCL as a percentage of LHFI excl. PPP and MW LOC (%) ALCL as a percentage of LHFI (%) ALCL ($) 2Q21 3Q21 4Q21 1Q22 2Q22 • Provision for credit loss expense for 2Q22 was $3.5 million, compared to a net benefit of $327,000 in 1Q22, and net benefit of $5.6 million in 2Q21. The increase in the provision expense during the current period is primarily due to growth in all portfolio segments of LHFI. • ALCL to nonperforming LHFI is 448.16% at 2Q22, 293.53% at 1Q22, and 252.78% at 2Q21. DOLLARS IN THOUSANDS, UNAUDITED 1.201.23 1.14

ORIGIN BANCORP, INC. _______ $1,896 $1 $12 $6 $10 $— At O r Abo ve Fl oo rs Belo w Fl oo r B y 1-2 5 b ps Belo w Fl oo r B y 26 -50 bp s Belo w Fl oo r B y 51 -75 bp s Belo w Fl oo r B y 76 -10 0 b ps Belo w Fl oo r B y >1 00 bp s $0 $1,000 $2,000 $3,000 $1.93 billion - total $1.90 billion 100% Beta $30.0 million "in the money" floors 14 LHFI: Fixed \ Variable (by Index) at 6/30/2022 Fixed: 45% Floating: 55% YIELDS, COSTS AND LHFI PROFILE Yield on LHFI (%) 4.00 4.05 4.11 4.08 4.26 3.97 3.98 3.94 3.95 4.21 3.25 3.25 3.25 3.29 3.94 0.10 0.09 0.09 0.23 1.02 Yield on LHFI Yield on LHFI excl. PPP Loans Avg. Prime Rate Avg. 1M LIBOR 2Q21 3Q21 4Q21 1Q22 2Q22 Cost of Funds (%) Impact of Floors on 1M LIBOR & Prime Indexed Loans(1) 98.48% 0.05% 0.61% 0.33% 0.51% 0.02% (1) Excluding Mortgage Warehouse Lines of Credit. 0.38 0.37 0.34 0.33 0.35 Cost of Total Deposits & Borrowings Cost of Interest Bearing Deposits Cost of Total Deposits 2Q21 3Q21 4Q21 1Q22 2Q22 0.31 0.30 0.28 0.26 0.22 0.21 0.19 0.17 0.19 0.29

ORIGIN BANCORP, INC. _______ 15 DOLLARS IN THOUSANDS, UNAUDITED 54,292 52,541 54,180 52,502 59,504 41,323 42,884 45,035 46,202 54,241 7,416 5,962 5,385 3,897 4,544 5,553 3,695 3,760 2,403 719 3.12 3.02 3.06 2.86 3.23 2.97 2.87 2.85 2.70 3.14 Net Interest Income excl. PPP & MW LOC ($) MW LOC Net Interest Income ($) PPP Net Interest Income ($) NIM (FTE) (%) NIM (FTE) excl. PPP & MW LOC (%) 2Q21 3Q21 4Q21 1Q22 2Q22 NET INTEREST INCOME AND NIM TRENDS 54,241 46,202 4,196 2,096 1,557 394 212 164 (282) (298) 1Q 22 RE Lo an s Inv es tm en t S ec . C&I E xc l P PP Non -M ar k. Equ ity Sec .-O the r F in. In sti . IB B al. D FB Othe r Sav ing s & IB Tr an sa cti on A cc ts. FH LB & O the r Bor ro wing s 2Q 22 45,000 50,000 55,000 3.14 2.70 0.25 0.14 0.07 0.03 0.02 (0.02) (0.02) (0.03) 1Q 22 IB B al. D FB RE Lo an s C&I e xc l. P PP Inv es tm en t S ec . Non -M ar k. Equ ity Sec .-O the r F in. In sti . Sav ing s & IB Tr an sa cti on A cc ts. FH LB & O the r Bor ro wing s Othe r 2Q 22 2.50 2.75 3.00 3.25 Net Interest Income Changes Excl. PPP and MW LOC - 2Q22 ($) NIM Changes Excl. PPP and MW LOC - 2Q22 (%) INIM

ORIGIN BANCORP, INC. _______ 1,030 1,133 1,505 1,662 1,869 1.83 1.76 1.63 1.59 1.85 Total Securities ($) Yield (%) 2Q21 3Q21 4Q21 1Q22 2Q22 Investment Securities Average Balance and Yield INVESTMENT SECURITIES DOLLARS IN MILLIONS, UNAUDITED • The available for sale securities portfolio ended the 2Q22 quarter with a net unrealized loss of $147.6 million, pre-tax, largely due to the steepening of the short end of the yield curve during the first half of the year. • The average balance of investment securities increased $206.6 million. Investment security purchases exceeded $500 million during 2022, with a weighted average yield of 2.06%. The majority of these purchases were during 1Q22. • Total portfolio weighted average effective duration was 4.39 years as of 6/30/2022. 16 18.9 11.9 5.7 (65.9) (116.0) 2Q21 3Q21 4Q21 1Q22 2Q22 Accumulated Other Comprehensive (Loss) Income(1) ($) Sector Fair Value % Market Price WAL Effective Duration Treasury/ Agency $ 257.0 14.2 % 96.52 2.81 2.66 MBS 759.9 42.2 94.39 5.32 4.28 CMO 229.6 12.7 93.96 5.88 4.12 Municipal 401.9 22.3 94.96 9.18 6.69 Corporate/ Other 156.0 8.6 94.72 5.70 3.20 Total $ 1,804.4 100 % 94.82 6.00 4.39 Available for Sale Securities (1) The accumulated other comprehensive (loss) income primarily represents the unrealized loss, net of tax benefit, of available for sale securities and is a component of equity.

ORIGIN BANCORP, INC. _______ Service Charges & Fees Mortgage Banking Revenue Insurance Commission & Fee Income Other 2Q183Q184Q181Q192Q193Q194Q191Q20 2Q203Q204Q201Q212Q213Q214Q211Q222Q22 17 Net Interest Income Noninterest Income 2Q18 3Q18 4Q18 1Q19 2Q19 3Q19 4Q19 1Q20 2Q20 3Q20 4Q20 1Q21 2Q21 3Q21 4Q21 1Q22 2Q22 Noninterest Income ($) Net Interest Income + Noninterest Income ($) NET REVENUE DISTRIBUTION DOLLARS IN THOUSANDS, UNAUDITED Components of Other Noninterest Income 73,720 10,615 2Q22 1Q22 4Q21 3Q21 2Q21 Gain on Fair Value of Lincoln Agency $ — $ — $ 5,200 $ — $ — BTH Merger Transaction Expenses 807 571 — — — Limited Partnership Investment Income 282 (363) 50 3,078 801 Swap Fee Income (loss)(1) 1 139 (285) 727 24 Valuation Income 1 (151) 11 (145) 125 Gain on Sale of Securities — — 75 — 5 Other 804 1,160 1,973 2,111 1,929 Total $ 1,895 $ 1,356 $ 7,024 $ 5,771 $ 2,884 (1) To benefit future income, the Company elected to unwind a one-way swap during the quarter ended December 31, 2021, and paid an early termination fee of $296,000. 47,785 14,216

ORIGIN BANCORP, INC. _______ 37,832 39,165 40,346 42,774 44,150 22,354 23,629 24,718 26,488 27,319 4,349 4,353 4,306 4,427 4,514 2,313 2,329 2,302 2,486 2,641 2,154 1,949 1,880 1,305 1,517 1,498 1,598 1,849 1,560 2,163 5,164 5,307 5,291 6,508 5,996 Salaries and Employee Benefits Occupancy and Equipment, net Data Processing Loan-related Expenses Office and Operations Other 2Q21 3Q21 4Q21 1Q22 2Q22 18 Efficiency Ratios (%) (1) NONINTEREST EXPENSE ANALYSIS DOLLARS IN THOUSANDS, UNAUDITED Noninterest Expense Composition ($) Consolidated Efficiency Ratio Adjusted Efficiency Ratio 2Q21 3Q21 4Q21 1Q22 2Q22 51 .5 0 % 53 .0 4 % 57 .2 1 % 52 .5 5 % 56 .9 2 % 62 .5 3 % 59 .8 9 % 59 .9 3 % 55 .3 5 % 56 .6 9 % Operating Leverage (%) (1) As used in this presentation, adjusted efficiency ratio is a non-GAAP financial measure. For a reconciliation of non-GAAP financial measures to their comparable GAAP measures, see slides 20-23 of this presentation. E FF IC IE N C Y R A TI O (% ) N IE / A V E R A G E A S S E TS (% ) 2.38 2.28 2.16 2.17 2.03 2.08 2.12 2.16 2.23 58.47 56.41 57.86 54.49 56.69 57.21 56.92 62.53 59.89 2Q20 4Q20 4Q20 1Q21 2Q21 3Q21 4Q21 1Q22 2Q22 40 60 80 100 1.5 2.0 2.5 3.0

ORIGIN BANCORP, INC. _______ 8.9 9.2 9.2 8.8 9.1 9.2 9.5 9.7 9.3 9.5 Company Level Bank Level 2Q21 3Q21 4Q21 1Q22 2Q22 11.2 11.4 11.4 11.3 10.9 11.6 11.8 12.0 11.9 11.4 Company Level Bank Level 2Q21 3Q21 4Q21 1Q22 2Q22 19 CAPITAL Bank Level Company Level Sub-debt Impact 14.9 15.0 14.8 14.6 14.0 13.9 14.0 14.1 13.9 13.3 Company Level Bank Level 2Q21 3Q21 4Q21 1Q22 2Q22 Tier 1 Capital to Average Assets (Leverage Ratio) Changes - 1Q22 (%)(1) 8.83 0.53 0.27 (0.05) (0.13) (0.11) (0.25) 1Q 22 Int ere st- be ari ng ba nk ba lan ce s Net Inc om e Othe r CRE AFS U nre ali ze d G ain A dju stm en t AFS S ec uri tie s 2Q 22 8.00 9.00 10.00 ICap ICap Total Capital to Risk-Weighted Assets (%)(1)Tier 1 Capital to Risk-Weighted Assets (%)(1) Tier 1 Capital to Average Assets (Leverage Ratio) (%)(1) (1) June 30, 2022, ratios are estimated. 9.09

ORIGIN BANCORP, INC. _______ Calculation of Core Deposits: 2Q22 1Q22 4Q21 3Q21 2Q21 1Q21 4Q20 3Q20 2Q20 Total Deposits $ 6,303,158 $ 6,767,179 $ 6,570,693 $ 6,158,768 $ 6,028,352 $ 6,346,194 $ 5,751,315 $ 5,935,925 $ 5,372,222 Less: Brokered Deposits — — — — — 571,673 431,180 835,902 490,881 Less: Time Deposits > $250K 200,469 213,861 222,656 245,312 264,566 276,629 271,272 275,112 311,256 Core Deposits $ 6,102,689 $ 6,553,318 $ 6,348,037 $ 5,913,456 $ 5,763,786 $ 5,497,892 $ 5,048,863 $ 4,824,911 $ 4,570,085 1Q20 4Q19 3Q19 2Q19 1Q19 4Q18 3Q18 2Q18 Total Deposits $ 4,556,246 $ 4,228,612 $ 4,284,317 $ 3,855,012 $ 3,898,248 $ 3,783,138 $ 3,727,158 $ 3,672,097 Less: Brokered Deposits 435,138 152,556 330,370 139,181 327,693 332,341 278,784 239,818 Less: Time Deposits > $250K 309,918 319,055 341,728 349,262 356,298 364,080 343,082 315,741 Core Deposits $ 3,811,190 $ 3,757,001 $ 3,612,219 $ 3,366,569 $ 3,214,257 $ 3,086,717 $ 3,105,292 $ 3,116,538 Calculation of PTPP Earnings: 2Q22 1Q22 4Q21 3Q21 2Q21 1Q21 4Q20 3Q20 2Q20 Net Income $ 21,311 $ 20,683 $ 28,322 $ 26,978 $ 27,733 $ 25,513 $ 17,552 $ 13,095 $ 4,957 Plus: Provision for Credit Losses 3,452 (327) (2,647) (3,921) (5,609) 1,412 6,333 13,633 21,403 Plus: Income Tax Expense 4,807 5,278 4,860 6,242 6,774 6,009 4,431 3,206 786 PTPP Earnings $ 29,570 $ 25,634 $ 30,535 $ 29,299 $ 28,898 $ 32,934 $ 28,316 $ 29,934 $ 27,146 1Q20 4Q19 3Q19 2Q19 1Q19 4Q18 3Q18 2Q18 Net Income $ 753 $ 12,827 $ 14,617 $ 12,283 $ 14,155 $ 13,178 $ 12,318 $ 12,702 Plus: Provision for Credit Losses 18,531 2,377 4,201 1,985 1,005 1,723 504 311 Plus: Income Tax Expense (427) 3,175 3,620 2,782 3,089 2,725 2,568 2,760 PTPP Earnings $ 18,857 $ 18,379 $ 22,438 $ 17,050 $ 18,249 $ 17,626 $ 15,390 $ 15,773 20 DOLLARS IN THOUSANDS, UNAUDITED RECONCILIATION OF NON-GAAP FINANCIAL MEASURES

ORIGIN BANCORP, INC. _______ Calculation of Tangible Book Value per Common Share(1): 2Q22 1Q22 4Q21 3Q21 2Q21 1Q21 4Q20 3Q20 2Q20 Total Common Stockholders' Equity $ 646,373 $ 676,865 $ 730,211 $ 705,667 $ 688,235 $ 656,355 $ 647,150 $ 627,637 $ 614,781 Less: Goodwill and Other Intangible Assets, net 50,053 50,578 51,330 29,830 30,024 30,246 30,480 30,717 30,953 Tangible Common Equity $ 596,320 $ 626,287 $ 678,881 $ 675,837 $ 658,211 $ 626,109 $ 616,670 $ 596,920 $ 583,828 Divided by Common Shares Outstanding at Period End 23,807,677 23,748,748 23,746,502 23,496,058 23,502,215 23,488,884 23,506,312 23,506,586 23,501,233 Tangible Book Value per Common Share $ 25.05 $ 26.37 $ 28.59 $ 28.76 $ 28.01 $ 26.66 $ 26.23 $ 25.39 $ 24.84 1Q20 4Q19 3Q19 2Q19 1Q19 4Q18 3Q18 2Q18 Total Common Stockholders' Equity $ 606,631 $ 599,362 $ 588,363 $ 584,293 $ 568,122 $ 549,779 $ 531,919 $ 519,356 Less: Goodwill and Other Intangible Assets, net 31,241 31,540 31,842 32,144 32,497 32,861 33,228 24,113 Tangible Common Equity $ 575,390 $ 567,822 $ 556,521 $ 552,149 $ 535,625 $ 516,918 $ 498,691 $ 495,243 Divided by Common Shares Outstanding at Period End 23,475,948 23,480,945 23,481,781 23,774,238 23,745,985 23,726,559 23,621,235 23,504,063 Tangible Book Value per Common Share $ 24.51 $ 24.18 $ 23.70 $ 23.22 $ 22.56 $ 21.79 $ 21.11 $ 21.07 Calculation of Adjusted Efficiency Ratio: 2Q22 1Q22 4Q21 3Q21 2Q21 1Q21 4Q20 3Q20 2Q20 Net Interest Income $ 59,504 $ 52,502 $ 54,180 $ 52,541 $ 54,292 $ 55,239 $ 51,819 $ 50,617 $ 46,290 Less: Insurance and Mortgage Net Interest Income 1,082 875 946 1,048 979 1,003 1,236 1,125 1,204 Total Noninterest Income 14,216 15,906 16,701 15,923 12,438 17,131 15,381 18,051 19,076 Less: Insurance and Mortgage Noninterest Income 8,047 10,552 5,683 6,179 5,815 8,348 9,326 12,741 13,826 Adjusted Total Revenue 64,591 56,981 64,252 61,237 59,936 63,019 56,638 54,802 50,336 Total Noninterest Expense 44,150 42,774 40,346 39,165 37,832 39,436 38,884 38,734 38,220 Less: Insurance and Mortgage Noninterest Expense 8,397 8,626 6,580 6,688 6,964 7,252 7,195 7,746 7,944 Adjusted Total Noninterest Expense 35,753 34,148 33,766 32,477 30,868 32,184 31,689 30,988 30,276 Adjusted Efficiency Ratio 55.35 % 59.93 % 52.55 % 53.03 % 51.50 % 51.07 % 55.95 % 56.55 % 60.15 % 1Q20 4Q19 3Q19 2Q19 1Q19 4Q18 3Q18 2Q18 Net Interest Income $ 42,810 $ 44,095 $ 44,622 $ 42,969 $ 42,026 $ 42,061 $ 39,497 $ 37,170 Less: Insurance and Mortgage Net Interest Income 872 735 776 457 346 409 359 189 Total Noninterest Income 12,144 10,818 12,880 11,176 11,604 10,588 10,237 10,615 Less: Insurance and Mortgage Noninterest Income 6,456 5,787 6,295 6,288 6,116 4,769 5,927 4,143 Adjusted Total Revenue 47,626 48,391 50,431 47,400 47,168 47,471 43,448 43,453 Total Noninterest Expense 36,097 36,534 35,064 37,095 35,381 35,023 34,344 32,012 Less: Insurance and Mortgage Noninterest Expense 6,463 6,432 6,435 6,343 6,096 6,429 7,055 5,670 Adjusted Total Noninterest Expense 29,634 30,102 28,629 30,752 29,285 28,594 27,289 26,342 Adjusted Efficiency Ratio 62.22 % 62.21 % 56.77 % 64.88 % 62.09 % 60.23 % 62.81 % 60.62 % 21 DOLLARS IN THOUSANDS, EXCEPT PER SHARE AMOUNTS, UNAUDITED RECONCILIATION OF NON-GAAP FINANCIAL MEASURES (1) A decline of $121.7 million in accumulated other comprehensive loss during the YTD period ended June 30, 2022, negatively impacted total stockholders' equity and tangible common equity and caused tangible book value per common share to decline by $5.11 primarily due to the steepening of the short end of the yield curve that occurred during 2022 and its impact on our investment portfolio, however it did not impact regulatory capital.

ORIGIN BANCORP, INC. _______ 2Q22 1Q22 2Q21 Calculation of PTPP Earnings: Net Income $ 21,311 $ 20,683 $ 27,733 Plus: Provision for Credit Losses 3,452 (327) (5,609) Plus: Income Tax Expense 4,807 5,278 6,774 PTPP Earnings $ 29,570 $ 25,634 $ 28,898 Calculation of PTPP ROAA and PTPP ROAE: PTPP Earnings $ 29,570 $ 25,634 $ 28,898 Divided by Number of Days in the Quarter 91 90 91 Multiplied by the Number of Days in the Year 365 365 365 Annualized PTPP Earnings $ 118,605 $ 103,960 $ 115,910 Divided by Total Average Assets $ 7,944,720 $ 8,045,246 $ 7,474,951 PTPP ROAA (Annualized) 1.49 % 1.29 % 1.55 % Divided by Total Average Stockholder's Equity $ 667,323 $ 722,504 $ 672,698 PTPP ROAE (Annualized) 17.77 % 14.39 % 17.23 % 22 DOLLARS IN THOUSANDS, UNAUDITED RECONCILIATION OF NON-GAAP FINANCIAL MEASURES

ORIGIN BANCORP, INC. _______ Six Months Ended June 30, 2022 June 30, 2021 Calculation of PTPP Earnings: Net Income $ 41,994 $ 53,246 Plus: Provision for Credit Losses 3,125 (4,197) Plus: Income Tax Expense 10,085 12,783 PTPP Earnings $ 55,204 $ 61,832 Calculation of PTPP ROAA and PTPP ROAE: PTPP Earnings $ 55,204 $ 61,832 Divided by Number of Days in the Quarter 181 181 Multiplied by the Number of Days in the Year 365 365 Annualized PTPP Earnings $ 111,323 $ 124,689 Divided by Total Average Assets $ 7,994,705 $ 7,428,978 PTPP ROAA 1.39 % 1.68 % Divided by Total Average Stockholder's Equity $ 694,761 $ 665,322 PTPP ROAE 16.02 % 18.74 % Calculation of Adjusted Efficiency Ratio: Net Interest Income $ 112,006 $ 109,531 Less: Insurance and Mortgage Net Interest Income 1,957 1,982 Noninterest Income 30,122 29,569 Less: Insurance and Mortgage Noninterest Income 18,599 14,163 Adjusted Total Revenue $ 121,572 $ 122,955 Total Noninterest Expense $ 86,924 $ 77,268 Less: Insurance and Mortgage Noninterest Expense 17,023 14,216 Adjusted Total Expense $ 69,901 $ 63,052 GAAP Efficiency Ratio 61.16 % 55.55 % Adjusted Efficiency Ratio 57.50 51.28 23 DOLLARS IN THOUSANDS, UNAUDITED RECONCILIATION OF NON-GAAP FINANCIAL MEASURES