Exhibit 99.1

500 Laurel Street Baton Rouge, LA 70801 Phone: 877.614.7600

BUSINESS FIRST BANCSHARES, INC., ANNOUNCES FINANCIAL RESULTS FOR Q1 2020

Baton Rouge, La. (April 28, 2020) – Business First Bancshares, Inc. (NASDAQ: BFST) (Business First), parent company of b1BANK, Baton Rouge, Louisiana, today announced its unaudited results for the quarter ended March 31, 2020, including net income of $4.5 million, or $0.34 per diluted share, decreases of $1.2 million and $0.07, respectively, from the quarter ended March 31, 2019. On a non-GAAP basis, core net income for the quarter ended March 31, 2020, which excludes noncore income and expenses, was $5.0 million, or $0.37 per diluted share, decreases of $655,000 and $0.04, respectively, from the quarter ended March 31, 2019. Both net income and diluted earnings per share were adversely impacted for the quarter ended March 31, 2020, by additional provision for loan losses related to the expected impact of the COVID-19 pandemic.

In response to the COVID-19 pandemic, Business First proactively assisted, and continues to assist, customers by deferring principal and/or interest payments on approximately 1,000 loans with an outstanding balance of $468 million as of April 19, 2020. Additionally, through April 19, 2020, Business First approved $250 million of Small Business Administration (SBA) Paycheck Protection Program (PPP) loans for approximately 1050 applicants.

“2020 opened with a sense of optimism. Our organization achieved solid growth in quality assets, continued to aggregate talented employees and announced a transformative acquisition,” said Jude Melville, president and CEO. “Clearly the end of the first quarter of this new year has been unexpected. While the foreseeable future is challenging, we also know the positives with which we started the year—strong relationships with clients, talented employees, a deeper, more liquid balance sheet-- will ultimately enable us to contribute to our region’s recovery.”

On April 23, 2020, Business First’s board of directors declared a quarterly dividend based upon financial performance for the first quarter in the amount of $0.10 per share, same as the prior quarter, to the common shareholders of record as of May 15, 2020. The dividend will be paid on May 31, 2020, or as soon thereafter as practicable.

Quarterly Highlights

Financial Condition

March 31, 2020, Compared to December 31, 2019

Loans

Total loans held for investment increased by $61.1 million compared to December 31, 2019, or 14.30% annualized, for the quarter ended March 31, 2020. The growth in the loan portfolio, on a percentage basis, was largely attributed to the commercial, real estate – construction and land, and real estate – farmland segments.

Business First’s unfunded commitments remained constant throughout the quarter, including March which was most impacted by the COVID-19 pandemic. Consequently, the increase in the loan portfolio was attributable to new loan originations, as draws on existing unfunded commitments were minimal.

Credit Quality

Nonperforming loans as a percentage of total loans held for investment increased from 0.53% as of December 31, 2019, to 0.57% as of March 31, 2020. The increase was attributable to an increase in past due loans of $762,000, of which $465,000 was attributable to a single commercial loan, and $324,000 in nonaccrual loans. Nonperforming assets as a percentage of total assets increased from 0.58% as of December 31, 2019, to 0.59% as of March 31, 2020.

Total Shareholders’ Equity

Book value per common share was $21.58 at March 31, 2020, compared to $21.47 at December 31, 2019. Total shareholders’ equity was impacted by $5.0 million of share repurchases, at an average weighted price of $11.50 per share, for the quarter ended March 31, 2020. Common equity to total assets remains strong at 12.33% at March 31, 2020.

March 31, 2020, Compared to March 31, 2019

Loans

Total loans held for investment increased by $185.2 million compared to March 31, 2019, or 11.7%. The growth in the loan portfolio was spread throughout many of the loan segments, although exposure was reduced in the real estate – multi-family residential and consumer segments.

Credit Quality

Nonperforming loans as a percentage of total loans held for investment decreased from 0.84% as of March 31, 2019, to 0.57% as of March 31, 2020. Nonperforming assets as a percentage of total assets decreased from 0.71% as of March 31, 2019, to 0.59% as of March 31, 2020.

Total Shareholders’ Equity

Book value per common share was $21.58 at March 31, 2020, compared to $20.14 at March 31, 2019.

Results of Operations

First Quarter 2020 Compared to Fourth Quarter 2019

Net Income and Diluted Earnings Per Share

For the quarter ended March 31, 2020, net income was $4.5 million, or $0.34 per diluted share, compared to net income of $5.8 million, or $0.42 per diluted share, for the quarter ended December 31, 2019. The decreases were largely attributable to the federal funds rate cuts of 150 basis point during March 2020, resulting in a decrease in net interest income, the increase in the provision for loan losses, largely attributable to the COVID-19 pandemic, and the increase in merger and conversion-related expenses, offset by a reduction in provision for income taxes attributable to stock option exercises and increase in other income.

On a non-GAAP basis, core net income, which excludes noncore income and expenses, for the quarter ended March 31, 2020, was $5.0 million, or $0.37 per diluted share, compared to core net income of $6.1 million, or $0.45 per diluted share, for the quarter ended December 31, 2019. Notable noncore events impacting earnings for the quarter ended March 31, 2020, included the incurrence of $126,000 in gains associated with the disposal of former bank premises and equipment in other income and $1.2 million in acquisition-related expenses, compared to the incurrence of $125,000 in losses associated with the disposal of former bank premises and equipment in other income related to the rebranding of b1BANK and a $216,000 adjustment to estimated provision for income taxes associated with the sale of the Mangham banking center for the quarter ended December 31, 2019.

Interest Income

For the quarter ended March 31, 2020, net interest income totaled $20.2 million and net interest margin and net interest spread were 3.93% and 3.55%, respectively, compared to $20.6 million, 4.08% and 3.65% for the quarter ended December 31, 2019. The average yield on the loan portfolio was 5.55% for the quarter ended March 31, 2020, compared to 5.82% for the quarter ended December 31, 2019. The average yield on total interest-earning assets was 5.06% for the quarter ended March 31, 2020, compared to 5.28% for the quarter ended December 31, 2019.

Average loan yield, average yield on total interest-earning assets, net interest margin, and net interest spread were impacted for the quarter ended March 31, 2020, by less discount accretion, lower yielding loans due to the federal funds rate cuts of 150 basis points during March, and one less day for the quarter ended March 31, 2020, compared to the quarter ended December 31, 2019. The impact to net interest margin and net interest spread was mitigated by a reduction in the overall cost of funds (which includes noninterest-bearing deposits).

Net interest margin and net interest spread (excluding loan discount accretion of $290,000) were 3.88% and 3.49%, respectively, for the quarter ended March 31, 2020, compared to 3.92% and 3.49% (excluding loan discount accretion of $800,000) for the quarter ended December 31, 2019.

Interest Expense

For the quarter ended March 31, 2020, overall cost of funds (which includes noninterest-bearing deposits) decreased by seven basis points, from 1.27% to 1.20%, compared to the quarter ended December 31, 2019. The decrease in cost of funds was largely attributable to an overall reduction in interest rates on b1BANK’s deposit offerings.

Other Income

For the quarter ended March 31, 2020, other income was impacted by an additional $230,000 in small business investment company (SBIC) investment income and $250,000 increase in gains/losses on sales of former premises and equipment compared to the quarter ended December 31, 2019.

Other Expense

For the quarter ended March 31, 2020, salaries and employee benefits increased $410,000 due to annual raises, tax on executive bonus, tax on stock option exercises and increased headcount of full-time equivalent employees from 355 to 367, offset by one less day during the quarter ended March 31, 2020, compared to the quarter ended December 31, 2019.

Other expenses increased by $1.1 million due to merger and conversion-related costs incurred during the quarter ended March 31, 2020, offset by a decrease of $379,000 in additional other real estate owned expenses and write-downs compared to the quarter ended December 31, 2019.

Provision for Loan Losses

During the quarter ended March 31, 2020, Business First recorded a provision for loan losses of $1.4 million, compared to $192,000 for the quarter ended December 31, 2019. The reserve for the quarter ended March 31, 2020, was impacted significantly by the expected impact of the COVID-19 pandemic. The increase related to COVID-19 was recorded through a qualitative adjustment. The provision for the quarter ended December 31, 2019, was lower due to tempered annualized loan growth of 3.67% during the quarter.

Return on Assets and Equity

Return on average assets and equity, each on an annualized basis, were 0.80% and 6.31%, respectively, for the quarter ended March 31, 2020, compared to 1.04% and 8.18%, respectively, for the quarter ended December 31, 2019.

First Quarter 2020 Compared to First Quarter 2019

Net Income and Diluted Earnings Per Share

For the quarter ended March 31, 2020, net income was $4.5 million, or $0.34 per diluted share, compared to net income of $5.7 million, or $0.41 per diluted share, for the quarter ended March 31, 2019. The decreases in net income and diluted earnings per share were mainly attributable to increased provision for loan losses, expenses in salaries and employee benefits, merger and conversion-related expenses, other real estate owned expenses and write-downs and other expenses, offset by an increase in net interest income, other income and reduction in provision for income taxes associated with stock option exercises.

On a non-GAAP basis, core net income, which excludes noncore income and expenses, for the quarter ended March 31, 2020, was $5.0 million, or $0.37 per diluted share, compared to core net income of $5.6 million, or $0.41 per diluted share, for the quarter ended March 31, 2019. Notable noncore events impacting earnings for the quarter ended March 31, 2020, included the incurrence of $126,000 in gains associated with the disposal of former bank premises and equipment in other income and $1.2 million in acquisition-related expenses.

Interest Income

For the quarter ended March 31, 2020, net interest income totaled $20.2 million and net interest margin and net interest spread were 3.93% and 3.55%, respectively, compared to $19.1 million, 4.01% and 3.61% for the quarter ended March 31, 2019. The average yield on the loan portfolio was 5.55% for the quarter ended March 31, 2020, compared to 5.79% for the quarter ended March 31, 2019. The average yield on total interest-earning assets was 5.06% for the quarter ended March 31, 2020, compared to 5.16% for the quarter ended March 31, 2019.

Average loan yield, average yield on total interest-earning assets, net interest margin, and net interest spread were impacted for the quarter ended March 31, 2020, largely by the federal funds rate cuts of 225 basis points which occurred throughout the second half of 2019 and first quarter of 2020.

Net interest margin and net interest spread (excluding loan discount accretion of $290,000) were 3.88% and 3.49%, respectively, for the quarter ended March 31, 2020, compared to 3.92% and 3.52% (excluding loan discount accretion of $432,000) for the quarter ended March 31, 2019.

Interest Expense

For the quarter ended March 31, 2020, overall cost of funds (which includes noninterest-bearing deposits) decreased by one basis point, from 1.21% to 1.20%, compared to the quarter ended March 31, 2019.

Other Income

For the quarter ended March 31, 2020, other income was impacted by $380,000 in SBIC investment income, $126,000 in gains on sales of former premises and equipment, and $177,000 of SBA loan sales, offset by reductions in correspondent bank income of $99,000 and rental income of $133,000.

Other Expense

For the quarter ended March 31, 2020, salaries and employee benefits increased $883,000 due to annual merit raises and increased headcount of full-time equivalent employees from 346 to 367 compared to the quarter ended March 31, 2019.

Other expenses increased for the quarter ended March 31, 2020, by $1.4 million in merger and conversion-related costs, $226,000 in additional other real estate owned expenses and write-downs, and approximately $141,000 in loan collection expenses compared to the quarter ended March 31, 2019.

Provision for Loan Losses

During the quarter ended March 31, 2020, Business First recorded a provision for loan losses of $1.4 million compared to $633,000 for the quarter ended March 31, 2019. The reserve for the quarter ended March 31, 2020, was impacted significantly by the expected impact of the COVID-19 pandemic. The increase related to COVID-19 was recorded through a qualitative adjustment.

Return on Assets and Equity

Return on average assets and return on average equity, each on an annualized basis, were 0.80% and 6.31%, respectively, for the quarter ended March 31, 2020, from 1.09% and 8.62%, respectively, for the quarter ended March 31, 2019.

About Business First Bancshares, Inc.

Business First Bancshares, Inc., through its banking subsidiary b1BANK, formerly known as Business First Bank, operates 26 banking centers in markets across Louisiana and in the Dallas, Texas area. b1BANK provides commercial and personal banking, treasury management and wealth solutions services to small to midsize businesses and their owners and employees. Visit www.b1BANK.com for more information. Business First’s common stock is traded on the NASDAQ Global Select Market under the symbol “BFST.”

Non-GAAP Financial Measures

This press release includes certain non-GAAP financial measures (e.g., referenced as “core” or “tangible” or “pre-tax, pre-provision”) intended to supplement, not substitute for, comparable GAAP measures. These measures typically adjust income available to common shareholders for certain significant activities or transactions that, in management’s opinion, can distort period-to-period comparisons of Business First’s performance. Transactions that are typically excluded from non-GAAP measures include realized and unrealized gains/losses on former bank premises and equipment, investment sales, impaired loan sales, acquisition-related expenses (including, but not limited to, legal costs, system conversion costs, severance and retention payments, etc.). Management believes presentations of these non-GAAP financial measures provide useful supplemental information that is essential to a proper understanding of the operating results of the Company’s core business. These non-GAAP disclosures are not necessarily comparable to non-GAAP measures that may be presented by other companies. Reconciliations of non-GAAP financial measures to GAAP financial measures are provided at the end of the tables below.

Special Note Regarding Forward-Looking Statements

Certain statements contained in this release may not be based on historical facts and are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These forward-looking statements may be identified by their reference to a future period or periods or by the use of forward-looking terminology such as “anticipate,” “believe,” “estimate,” “expect,” “may,” “might,” “will,” “would,” “could” or “intend.” We caution you not to place undue reliance on the forward-looking statements contained in this news release, in that actual results could differ materially from those indicated in such forward-looking statements as a result of a variety of factors, including those factors specified in our Annual Report on Form 10-K and other public filings. Actual results will also be significantly impacted by the effects of the ongoing COVID-19 pandemic, including, among other effects: the impact of the public health crisis; the extent and duration of closures of businesses, including our branches, vendors and customers; the operation of financial markets; employment levels; market liquidity; the impact of various actions taken in response by the U.S. federal government, the Federal Reserve, other banking regulators, state and local governments; the adequacy of our allowance for loan losses in relation to potential losses in our loan portfolio; and the impact that all of these factors have on our borrowers, other customers, vendors and counterparties. We undertake no obligation to update these forward-looking statements to reflect events or circumstances that occur after the date of this news release.

Additional Information

For additional information on Business First, you may obtain Business First’s reports that are filed with the Securities and Exchange Commission (SEC) free of charge by using the SEC’s EDGAR service on the SEC’s website at www.sec.gov or by contacting the SEC for further information at 1-800-SEC-0330. Alternatively, these documents can be obtained free of charge from Business First by directing a request to: Business First Bancshares, Inc., 500 Laurel Street, Suite 101, Baton Rouge, Louisiana 70801, Attention: Corporate Secretary.

No Offer or Solicitation

This release does not constitute or form part of any offer to sell, or a solicitation of an offer to purchase, any securities of the Company. There will be no sale of securities in any jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such jurisdiction.