EXHIBIT 99.1

SOUTHSIDE BANCSHARES, INC.

ANNOUNCES FINANCIAL RESULTS FOR THE

FIRST QUARTER ENDED MARCH 31, 2020

• First quarter provision for credit losses of $25.2 million; largely worsening economic forecast, COVID-19 related;

• Linked quarter loans increased$32.8 million, or 0.9%, to $3.60 billion from $3.57 billion;

• Linked quarter nonperforming assets as a percent of total assets decreased to 0.24% from 0.26%;

• Linked quarter tax-equivalent net interest margin⁽¹⁾ increased 5 basis points to 3.03% from 2.98%.

Tyler, Texas (May 5, 2020) Southside Bancshares, Inc. (“Southside” or the “Company”) (NASDAQ:SBSI) today reported its financial results for the quarter ended March 31, 2020. Southside reported net income of $4.0 million for the three months ended March 31, 2020, a decrease of $14.9 million, or 79.0%, compared to $18.8 million for the same period in 2019. Earnings per diluted common share decreased$0.44, or 78.6%, to $0.12 for the three months ended March 31, 2020, from $0.56 for the same period in 2019. The annualized return on average shareholders’ equity for the three months ended March 31, 2020 was 1.93%, compared to 10.35% for the same period in 2019.  The annualized return on average assets was 0.23% for the three months ended March 31, 2020, compared to 1.21% for the same period in 2019.

“Our financial results reflect the strength of our sound credit quality, liquidity, capital position and solid operating fundamentals,” stated Lee R. Gibson, President and Chief Executive Officer of Southside. “We are pleased to report net income of $4.0 million, and earnings per share of $0.12, after adopting ASU 2016-13⁽²⁾ (“CECL”) and recording a $25.2 million provision for credit losses due largely to a worsening economic forecast related to COVID-19. On a linked quarter basis, nonperforming assets as a percent of total assets decreased to 0.24%, and the tax equivalent net interest margin improved five basis points. COVID-19 significantly impacted business operations throughout the United States in the first quarter, banking included, and is expected to continue to impact our business, as well as our customers' businesses. I am proud of how our Southside team embraced the necessary and evolving changes and continued to provide outstanding customer service. Through the Paycheck Protection Program (“PPP”), implemented in April, the Southside team processed approximately 2,000 small business loans, totaling just over $300 million as of April 30, 2020. Additionally, we are assisting our borrowers that may be experiencing financial hardship due to COVID-19 related challenges with payment deferrals, generally for up to three months. As of April 30, 2020, payment deferrals represented $176.7 million of our outstanding loan balances with the largest categories including commercial real estate loans of $112.7 million and 1-4 family residential loans of $47.2 million.”

“While loans increased $32.8 million during the quarter, at this time, other than short-term PPP loan growth, we do not anticipate meaningful loan growth for the remainder of the year due to the current COVID-19 related economic forecast for 2020. Due to the reduced expectations for 2020 loan growth and the significant declines in short and long-term interest rates, we increased our securities portfolio approximately $450 million and entered into an additional $400 million of swaps to lock in long-term interest rates on funding. The interest rate swap contracts had an average interest rate of 0.32% with an average weighted maturity of 5.2 years at March 31, 2020. During March, as volatility in equity markets persisted, U.S. agency mortgage-backed securities and highly rated municipal bonds also began to experience volatility primarily due to illiquidity. When this occurred, we increased the securities portfolio by purchasing $491 million of largely AAA rated municipal bonds of which $8 million were taxable, at levels we believe are attractive. Other security purchases and sales during the quarter were designed to increase the overall yield of the securities portfolio. Due to the timing of these transactions the full impact on interest income and expense will be reflected in future quarters.”

“As the COVID-19 pandemic began to unfold during the quarter, our primary concern was and remains, the safety of our customers and employees, and to that end, we implemented various plans and procedures to achieve that priority as well as continue to provide the quality of service our customers have grown accustomed to. While some of our methods and delivery channels of services have changed temporarily, the high level of quality service our customers expect and deserve has continued. At this time when our country has suffered record job losses, I am very thankful to be able to report that we have not furloughed or laid off any employees as a result of COVID-19. Later in 2020, Southside will celebrate its 60th Anniversary. Over the course of these 60 years, we have seen growth not only in our balance sheet and capital position, but also in the relationships we have formed in the communities we serve. As a result, we believe we are well positioned to navigate these difficult times and emerge eager and ready to help our customers achieve their financial goals.”

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Operating Results for the Three Months Ended March 31, 2020

Net income was $4.0 million for the three months ended March 31, 2020, compared to $18.8 million for the same period in 2019, a decrease of $14.9 million, or 79.0%. Earnings per diluted common share were $0.12 for the three months ended March 31, 2020, compared to $0.56 for the same period in 2019, a decrease of 78.6%. The decrease in net income was driven by increases in the provision for credit losses and noninterest expense, partially offset by increases in interest income and noninterest income as well as decreases in interest expense and income tax expense. The increase in the provision for credit losses for the quarter was primarily due to the recent developments related to COVID-19 and the resulting impact on the economic assumptions used in the CECL model. The adoption of CECL⁽²⁾ replaced the incurred loss model with an expected credit loss methodology. Annualized returns on average assets and average shareholders’ equity for the three months ended March 31, 2020 were 0.23% and 1.93%, respectively.  Our efficiency ratio (FTE)⁽¹⁾ was 51.91% for the three months ended March 31, 2020.

Net interest income for the three months ended March 31, 2020 was $44.7 million, compared to $41.1 million during the same period in 2019, an increase of $3.6 million, or 8.7%. Linked quarter, net interest income increased $1.5 million, or 3.5%, compared to $43.2 million during the three months ended December 31, 2019. The increase in net interest income compared to the same period in 2019 and the linked quarter, was due primarily to the decrease in interest expense on our interest bearing liabilities, a result of lower funding costs on our interest bearing liabilities, and an increase in interest income due to a higher average balance of our interest earning assets during the three months ended March 31, 2020.

Our tax equivalent net interest margin⁽¹⁾ was 3.03% for the three months ended March 31, 2020, compared to 3.07% for the same period in 2019. The decrease was due to the decrease in average yield on interest earning assets of 27 basis points, partially offset by a decrease in average rate paid on interest bearing liabilities. Our tax equivalent net interest margin increased five basis points compared to 2.98% for the three months ended December 31, 2019. This increase was due to a decrease in the average rate paid on interest bearing liabilities of 16 basis points and the increase in average interest earning assets.

Noninterest income was $15.5 million for the three months ended March 31, 2020, an increase of 62.5%, compared to $9.5 million for the same period in 2019. The increase was primarily due to increases in net gain on sale of securities available for sale, other noninterest income and deposit services income, partially offset by decreases in trust fees. On a linked quarter basis, noninterest income increased$5.0 million, or 48.1%, due to a $5.5 million increase in net gain on sale of securities available for sale, partially offset by decreases in deposit services income and trust fees.

Noninterest expense was $30.5 million for the three months ended March 31, 2020, compared to $29.6 million for the same period in 2019, an increase of $0.9 million, or 3.0%. The increase was primarily due to increases in salaries and employee benefits, partially offset by decreases in FDIC insurance, other noninterest expense and amortization of intangibles. On a linked quarter basis, noninterest expense decreased$0.4 million, or 1.4%, compared to the three months ended December 31, 2019. The decrease was due to a decrease in losses incurred on the disposition of certain assets of approximately $0.6 million, included in other noninterest expense, partially offset by increases in salaries and employee benefits.

Income tax expense decreased $2.7 million for the three months ended March 31, 2020, compared to the same period in 2019. Our effective tax rate (“ETR”) was approximately 10.8% and 14.3% for the three months ended March 31, 2020 and 2019, respectively. On a linked quarter basis, income tax expense decreased $2.4 million, or 83.2%, compared to the three months ended December 31, 2019. The lower ETR for the three months ended March 31, 2020, as compared to the same period in 2019, was primarily due to an increase in tax-exempt income as a percentage of pre-tax income.

Balance Sheet Data

At March 31, 2020, we had $7.27 billion in total assets, compared to $6.75 billion at December 31, 2019 and $6.22 billion at March 31, 2019.

Loans at March 31, 2020 were $3.60 billion, an increase of $295.9 million, or 9.0%, compared to $3.31 billion at March 31, 2019. Linked quarter loans increased$32.8 million, or 0.9%, from $3.57 billion at December 31, 2019. The linked quarter net increase in our loans consisted primarily of an increase of $100.6 million of commercial real estate loans, partially offset by decreases of $41.0 million of construction loans, $17.5 million of commercial loans, $8.0 million of municipal loans and $1.6 million of loans to individuals.

Securities at March 31, 2020 were $2.95 billion, an increase of $923.8 million, or 45.7%, compared to $2.02 billion at March 31, 2019. Approximately half of the increase occurred during the first quarter of 2020, with the remainder of the increase occurring during each of the last three quarters of 2019. Linked quarter, securities increased $454.1 million, or 18.2%, from $2.49 billion at December 31, 2019 due to the purchase of tax free municipal bonds and to a lesser extent, taxable municipal bonds.

Deposits at March 31, 2020 were $4.74 billion, an increase of $171.2 million, or 3.7%, compared to $4.57 billion at March 31,

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2019. Linked quarter, deposits increased $36.4 million, or 0.8%, from $4.70 billion at December 31, 2019, primarily due to an increase in public fund deposits.

On March 12, 2020, the Board of the Company increased its authorization under the Stock Repurchase Plan (the “Plan”), previously authorized in September 2019, by an additional 1.0 million shares, for a total authorization to repurchase up to 2.0 million shares. As of March 31, 2020, we purchased 895,338 shares at an average price of $29.82, resulting in approximately 1.1 million authorized shares remaining. Subsequent to March 31, 2020, there have been no additional purchases.

CECL Adoption and Asset Quality

During the first quarter, we adopted ASU 2016-13, Financial Instruments - Credit Losses, often referred to as CECL. Upon the adoption of CECL, we recorded a cumulative-effect adjustment that decreased retained earnings by $7.8 million, net of tax. This adjustment was the result of a $5.3 million increase in the allowance for loan losses, from $24.8 million at December 31, 2019 to $30.1 million upon adoption, including $0.2 million for purchased loans with credit deterioration, and a $4.8 million increase in other liabilities related to the allowance for off-balance-sheet credit exposures.

Based on the credit quality of our securities portfolio, the adoption of CECL did not result in the recording of an allowance for credit losses on our held-to-maturity securities.

Nonperforming assets at March 31, 2020 were $17.4 million, or 0.24% of total assets, a decrease of $20.7 million, or 54.3%, compared to $38.1 million, or 0.61% of total assets, at March 31, 2019, and a slight decrease from $17.4 million, or 0.26% of total assets, at December 31, 2019. During the three months ended March 31, 2020, nonaccrual loans increased $0.3 million, or 5.2%.

The allowance for loan losses increased to $53.6 million, or 1.49% of total loans at March 31, 2020, compared to $24.8 million, or 0.69% of total loans, at December 31, 2019, due to the adoption of CECL and the economic uncertainty related to the COVID-19 pandemic and resulting expected losses.

For the three months ended March 31, 2020, we recorded provision for credit losses on loans of $24.1 million, compared to a reversal of provision for loan losses of $0.9 million for the three months ended March 31, 2019 and a provision for loan losses of $2.5 million for the three months ended December 31, 2019. The increase during the first quarter of 2020 was primarily due to the application of the CECL model and the economic impact of COVID-19 on macroeconomic factors used in the CECL methodology, including the potential for credit deterioration. If the COVID-19 pandemic and economic impact is prolonged, it is likely that credit losses and nonperforming assets may increase. Net charge-offs were $0.5 million for the three months ended March 31, 2020, compared to net charge-offs of $1.9 million for the three months ended March 31, 2019 and $2.8 million of net charge-offs for the three months ended December 31, 2019.

For the three months ended March 31, 2020, we recorded provision for credit losses on off-balance-sheet credit exposures of $1.2 million, compared to a reversal of provision of $56,000 for the three months ended March 31, 2019 and a reversal of provision of $85,000 for the three months ended December 31, 2019. The balance of the allowance for off-balance-sheet credit exposures at March 31, 2020 was $7.5 million, and is included in other liabilities.

Dividend

Southside Bancshares, Inc. declared a first quarter cash dividend of $0.31 per share on February 6, 2020, which was paid on March 5, 2020, to all shareholders of record as of February 20, 2020.

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(1) Refer to “Non-GAAP Financial Measures” below and to “Non-GAAP Reconciliation” at the end of the financial statement tables in this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

(2) We adopted ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” on January 1, 2020. ASU 2016-13 replaced the incurred loss model with an expected loss methodology that is referred to as current expected credit loss. Adoption of this guidance on January 1, 2020, resulted in a cumulative-effect adjustment to reduce retained earnings by $7.8 million, net of tax. Due to the adoption of the guidance under the modified retrospective approach, prior periods have not been adjusted and thus may not be comparable.

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Conference Call

Southside's management team will host a conference call to discuss its first quarter ended March 31, 2020 financial results on Tuesday, May 5, 2020 at 9:00 a.m. CDT.  The call can be accessed by dialing 844-775-2540 and by identifying the conference ID number 3290996 or by identifying “Southside Bancshares, Inc., First Quarter 2020 Earnings Call.”  To listen to the call via webcast, register at https://investors.southside.com.

For those unable to listen to the conference call live, a recording will be available from approximately 12:00 p.m. CDT May 5, 2020 through 12:00 p.m. CDT May 17, 2020 by accessing the company website, https://investors.southside.com.

Non-GAAP Financial Measures

Our accounting and reporting policies conform to generally accepted accounting principles (“GAAP”) in the United States and prevailing practices in the banking industry. However, certain non-GAAP measures are used by management to supplement the evaluation of our performance. These include the following fully taxable-equivalent measures (“FTE”): (i) Net interest income (FTE), (ii) Net interest margin (FTE), (iii) Net interest spread (FTE), and (iv) Efficiency ratio (FTE), which include the effects of taxable-equivalent adjustments using a federal income tax rate of 21% for the three months ended March 31, 2020 and 2019 to increase tax-exempt interest income to a tax-equivalent basis. Interest income earned on certain assets is completely or partially exempt from federal income tax. As such, these tax-exempt instruments typically yield lower returns than taxable investments.

Net interest income (FTE), Net interest margin (FTE) and Net interest spread (FTE). Net interest income (FTE) is a non-GAAP measure that adjusts for the tax-favored status of net interest income from certain loans and investments. We believe this measure to be the preferred industry measurement of net interest income and it enhances comparability of net interest income arising from taxable and tax-exempt sources. The most directly comparable financial measure calculated in accordance with GAAP is our net interest income. Net interest margin (FTE) is the ratio of net interest income (FTE) to average earning assets. The most directly comparable financial measure calculated in accordance with GAAP is our net interest margin. Net interest spread (FTE) is the difference in the average yield on average earning assets on a tax-equivalent basis and the average rate paid on average interest bearing liabilities. The most directly comparable financial measure calculated in accordance with GAAP is our net interest spread.

Efficiency ratio (FTE).  The efficiency ratio (FTE) is a non-GAAP measure that provides a measure of productivity in the banking industry. This ratio is calculated to measure the cost of generating one dollar of revenue. The ratio is designed to reflect the percentage of one dollar which must be expended to generate that dollar of revenue. We calculate this ratio by dividing noninterest expense, excluding amortization expense on intangibles and certain nonrecurring expense by the sum of net interest income (FTE) and noninterest income, excluding net gain (loss) on sale of securities available for sale and certain nonrecurring impairments. The most directly comparable financial measure calculated in accordance with GAAP is our efficiency ratio.

These non-GAAP financial measures should not be considered alternatives to GAAP-basis financial statements and other bank holding companies may define or calculate these non-GAAP measures or similar measures differently. Whenever we present a non-GAAP financial measure in an SEC filing, we are also required to present the most directly comparable financial measure calculated and presented in accordance with GAAP and reconcile the differences between the non-GAAP financial measure and such comparable GAAP measure.

Management believes adjusting net interest income, net interest margin and net interest spread to a fully taxable-equivalent basis is a standard practice in the banking industry as these measures provide useful information to make peer comparisons. Tax-equivalent adjustments are reflected in the respective earning asset categories as listed in the “Average Balances with Average Yields and Rates” tables.

A reconciliation of our non-GAAP financial measures to the comparable GAAP financial measures is included at the end of the financial statement tables.

About Southside Bancshares, Inc.

Southside Bancshares, Inc. is a bank holding company with approximately $7.27 billion in assets as of March 31, 2020, that owns 100% of Southside Bank.  Southside Bank currently has 60 branches in Texas and operates a network of 82 ATMs/ITMs.

During March 2020, the World Health Organization declared the novel strain of coronavirus (“COVID-19”) a global pandemic in response to the rapidly growing outbreak of the virus. COVID-19 has significantly impacted local, national and global economies due to stay-at-home orders and social distancing guidelines. In compliance with social distancing guidelines issued by federal, state and local governments, we closed all of our grocery store branches. As stay-at-home orders were issued by local governments

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in our market areas to combat the spread of the virus, we closed all traditional lobbies and wealth management and trust offices to walk-in customers, however, most of these traditional locations are offering certain services by appointment only. All other banking services, including our motor banks, ATMs/ITMs and automated telephone, internet and mobile banking products are available to serve our customers.

To learn more about Southside Bancshares, Inc., please visit our investor relations website at https://investors.southside.com. Our investor relations site provides a detailed overview of our activities, financial information and historical stock price data.  To receive e-mail notification of company news, events and stock activity, please register on the E-mail Notification portion of the website.  Questions or comments may be directed to Lindsey Bailes at (903) 630-7965, or lindsey.bailes@southside.com.

Forward-Looking Statements

Certain statements of other than historical fact that are contained in this press release and in other written material, documents and oral statements issued by or on behalf of the Company may be considered to be “forward-looking statements” within the meaning of and subject to the safe harbor protections of the Private Securities Litigation Reform Act of 1995.  These forward-looking statements are not guarantees of future performance, nor should they be relied upon as representing management’s views as of any subsequent date.  These statements may include words such as “expect,” “estimate,” “project,” “anticipate,” “appear,” “believe,” “could,” “should,” “may,” “likely,” “intend,” “probability,” “risk,” “target,” “objective,” “plans,” “potential,” and similar expressions.  Forward-looking statements are statements with respect to the Company’s beliefs, plans, expectations, objectives, goals, anticipations, assumptions and estimates about the Company's future performance and are subject to significant known and unknown risks and uncertainties, which could cause the Company's actual results to differ materially from the results discussed in the forward-looking statements.  For example, discussions about trends in asset quality, capital, liquidity, the pace of loan and revenue growth, the Company's ability to sell nonperforming assets, expense reductions, planned operational efficiencies, earnings, successful integration of completed acquisitions and certain market risk disclosures, including the impact of interest rates, tax reform and other economic factors, are based upon information presently available to management and are dependent on choices about key model characteristics and assumptions and are subject to various limitations.  By their nature, certain of the market risk disclosures are only estimates and could be materially different from what actually occurs in the future.  The most recent factor that could cause future results to differ materially from those anticipated by our forward-looking statements include the negative impact of the novel coronavirus (“COVID-19”) pandemic on our business, financial position, operations and prospects, including our ability to continue our business activities in certain communities we serve, the duration of the pandemic and its continued effects on financial markets, a reduction in financial transactions and business activities resulting in decreased deposits and reduced loan originations, increases in unemployment rates impacting our borrowers' ability to repay their loans, our ability to manage liquidity in a rapidly changing and unpredictable market, additional interest rate changes by the Federal Reserve and other government actions in response to the pandemic, including additional quarantines, regulations or laws enacted to counter the effects of the COVID-19 pandemic on the economy.

Additional information concerning the Company and its business, including additional factors that could materially affect the Company’s financial results, is included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, under “Part I - Item 1. Forward Looking Information” and "Part I - Item 1A. Risk Factors" and in the Company’s other filings with the Securities and Exchange Commission.  The Company disclaims any obligation to update any factors or to announce publicly the result of revisions to any of the forward-looking statements included herein to reflect future events or developments.

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Southside Bancshares, Inc.

Consolidated Financial Summary (Unaudited)

(Dollars in thousands)

	As of
	2020			2019
	Mar 31,			Dec 31,			Sep 30,			Jun 30,			Mar 31,
ASSETS
Cash and due from banks	$	71,727		$	66,949		$	92,300		$	77,319		$	81,981
Interest earning deposits	40,486			43,748			22,524			54,642			184,612
Federal funds sold	—			—			—			560			3,350
Securities available for sale, at estimated fair value	2,813,024			2,358,597			2,240,381			2,088,787			1,876,255
Securities held to maturity, at net carrying value	134,491			134,863			140,955			147,091			147,431
Total securities	2,947,515			2,493,460			2,381,336			2,235,878			2,023,686
Federal Home Loan Bank stock, at cost	54,696			50,087			45,039			44,718			35,269
Loans held for sale	1,830			383			1,000			1,812			384
Loans	3,601,002			3,568,204			3,499,917			3,460,143			3,305,110
Less: Allowance for loan losses	(53,638		)	(24,797		)	(25,129		)	(24,705		)	(24,155		)
Net loans	3,547,364			3,543,407			3,474,788			3,435,438			3,280,955
Premises & equipment, net	146,212			143,912			141,683			140,105			138,290
Goodwill	201,116			201,116			201,116			201,116			201,116
Other intangible assets, net	12,381			13,361			14,391			15,471			16,600
Bank owned life insurance	101,066			100,498			99,916			99,294			98,704
Other assets	149,245			91,992			67,982			66,517			152,249
Total assets	$	7,273,638		$	6,748,913		$	6,542,075		$	6,372,870		$	6,217,196
LIABILITIES AND SHAREHOLDERS' EQUITY
Noninterest bearing deposits	$	1,065,708		$	1,040,112		$	1,038,695		$	1,028,861		$	1,038,116
Interest bearing deposits	3,673,415			3,662,657			3,452,072			3,450,395			3,529,777
Total deposits	4,739,123			4,702,769			4,490,767			4,479,256			4,567,893
Other borrowings and Federal Home Loan Bank borrowings	1,492,270			1,001,102			988,577			849,821			628,498
Subordinated notes, net of unamortized debt issuance costs	98,619			98,576			98,532			98,490			98,448
Trust preferred subordinated debentures, net of unamortized debt issuance costs	60,251			60,250			60,249			60,248			60,247
Other liabilities	87,575			81,636			93,497			97,290			104,077
Total liabilities	6,477,838			5,944,333			5,731,622			5,585,105			5,459,163
Shareholders' equity	795,800			804,580			810,453			787,765			758,033
Total liabilities and shareholders' equity	$	7,273,638		$	6,748,913		$	6,542,075		$	6,372,870		$	6,217,196

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Southside Bancshares, Inc.

Consolidated Financial Highlights (Unaudited)

(Dollars and shares in thousands, except per share data)

	Three Months Ended
	2020			2019
	Mar 31,			Dec 31,			Sep 30,			Jun 30,			Mar 31,
Income Statement:
Total interest income	$	60,752		$	60,533		$	60,555		$	60,672		$	59,027
Total interest expense	16,051			17,357			18,182			17,541			17,902
Net interest income	44,701			43,176			42,373			43,131			41,125
Provision for credit losses (1)	25,247			2,508			1,005			2,506			(918		)
Net interest income after provision for credit losses	19,454			40,668			41,368			40,625			42,043
Noninterest income
Deposit services	6,279			6,647			6,753			6,652			5,986
Net gain on sale of securities available for sale	5,541			42			42			416			256
Gain on sale of loans	170			104			131			181			93
Trust fees	1,305			1,685			1,523			1,520			1,541
Bank owned life insurance	569			582			622			559			544
Brokerage services	580			531			555			477			517
Other	1,054			874			1,485			1,449			601
Total noninterest income	15,498			10,465			11,111			11,254			9,538
Noninterest expense
Salaries and employee benefits	19,643			19,406			18,388			17,891			18,046
Net occupancy	3,311			3,234			3,430			3,289			3,175
Advertising, travel & entertainment	832			791			593			733			847
ATM expense	224			236			232			246			180
Professional fees	1,195			1,142			1,192			1,069			1,314
Software and data processing	1,227			1,259			1,116			1,086			1,076
Communications	493			485			480			489			487
FDIC insurance	25			—			—			437			422
Amortization of intangibles	980			1,030			1,080			1,129			1,179
Other (1)	2,590			3,361			2,515			3,331			2,901
Total noninterest expense	30,520			30,944			29,026			29,700			29,627
Income before income tax expense	4,432			20,189			23,453			22,179			21,954
Income tax expense	479			2,854			3,661			3,569			3,137
Net income	$	3,953		$	17,335		$	19,792		$	18,610		$	18,817
Common Share Data:
Weighted-average basic shares outstanding	33,691			33,790			33,773			33,726			33,697
Weighted-average diluted shares outstanding	33,805			33,934			33,901			33,876			33,846
Common shares outstanding end of period	33,012			33,823			33,795			33,749			33,718
Earnings per common share
Basic	$	0.12		$	0.51		$	0.59		$	0.55		$	0.56
Diluted	0.12			0.51			0.58			0.55			0.56
Book value per common share	24.11			23.79			23.98			23.34			22.48
Tangible book value per common share (2)	17.64			17.45			17.60			16.92			16.02
Cash dividends paid per common share	0.31			0.34			0.31			0.31			0.30
Selected Performance Ratios:
Return on average assets	0.23		%	1.03		%	1.23		%	1.20		%	1.21		%
Return on average shareholders’ equity	1.93			8.42			9.78			9.68			10.35
Return on average tangible common equity (2)	3.11			11.97			13.96			14.12			15.44
Average yield on earning assets (FTE) (2)	4.06			4.12			4.28			4.42			4.33
Average rate on interest bearing liabilities	1.30			1.46			1.60			1.61			1.62
Net interest spread (FTE) (2)	2.76			2.66			2.68			2.81			2.71
Net interest margin (FTE) (2)	3.03			2.98			3.03			3.17			3.07
Average earning assets to average interest bearing liabilities	126.22			128.00			128.33			128.99			127.70
Noninterest expense to average total assets	1.78			1.85			1.80			1.91			1.91
Efficiency ratio (FTE) (2)	51.91			53.87			50.53			51.44			53.66

(1) Upon adoption of CECL on January 1, 2020, the provision for credit losses is the sum of the provision for loan losses and the provision for off-balance-sheet credit exposures. Prior to the adoption of CECL, the provision for off-balance-sheet credit exposures was included in other noninterest expense.

(2) Refer to “Non-GAAP Reconciliation” at the end of the financial statement tables in this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

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Southside Bancshares, Inc.

Consolidated Financial Highlights (Unaudited)

(Dollars in thousands)

	Three Months Ended
	2020			2019
	Mar 31,			Dec 31,			Sep 30,			Jun 30,			Mar 31,
Nonperforming Assets:	$	17,403		$	17,449		$	29,747		$	29,363		$	38,111
Nonaccrual loans (1)	5,221			4,963			17,148			16,376			17,691
Accruing loans past due more than 90 days (1)	—			—			—			—			7,927
Troubled debt restructured loans (2)	11,448			12,014			11,683			11,918			11,490
Other real estate owned	734			472			912			1,069			978
Repossessed assets	—			—			4			—			25
Asset Quality Ratios:
Nonaccruing loans to total loans	0.14		%	0.14		%	0.49		%	0.47		%	0.54		%
Allowance for loan losses to nonaccruing loans	1,027.35			499.64			146.54			150.86			136.54
Allowance for loan losses to nonperforming assets	308.21			142.11			84.48			84.14			63.38
Allowance for loan losses to total loans	1.49			0.69			0.72			0.71			0.73
Nonperforming assets to total assets	0.24			0.26			0.45			0.46			0.61
Net charge-offs (recoveries) to average loans	0.06			0.32			0.07			0.23			0.24
Capital Ratios:
Shareholders’ equity to total assets	10.94			11.92			12.39			12.36			12.19
Common equity tier 1 capital	12.81			14.07			14.19			14.02			14.38
Tier 1 risk-based capital	14.13			15.46			15.61			15.46			15.88
Total risk-based capital	17.35			18.43			18.65			18.52			19.06
Tier 1 leverage capital	9.45			10.18			10.46			10.48			10.18
Period end tangible equity to period end tangible assets (3)	8.25			9.03			9.40			9.28			9.01
Average shareholders’ equity to average total assets	11.94			12.28			12.54			12.36			11.70

(1) Prior to the adoption of CECL, excluded purchased credit impaired loans measured at fair value at acquisition if the timing and amount of cash flows expected to be collected from those sales could be reasonably estimated.

(2) Prior to the adoption of CECL, included $0.8 million, $0.8 million, $0.8 million and $0.7 million in PCI loans restructured as of December 31, 2019, September 30, 2019, June 30, 2019 and March 31, 2019, respectively.

(3) Refer to the “Non-GAAP Reconciliation” at the end of the financial statement tables in this Earnings Release for a reconciliation of this non-GAAP financial measure to the nearest GAAP financial measure.

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Southside Bancshares, Inc.

Consolidated Financial Highlights (Unaudited)

(Dollars and shares in thousands, except per share data)

	Three Months Ended
	2020			2019
Loan Portfolio Composition	Mar 31,			Dec 31,			Sep 30,			Jun 30,			Mar 31,
Real Estate Loans:
Construction	$	603,952		$	644,948		$	621,040		$	579,565		$	603,411
1-4 Family Residential	787,875			787,562			792,638			782,073			786,198
Commercial	1,350,818			1,250,208			1,236,307			1,251,248			1,104,378
Commercial Loans	383,984			401,521			382,077			389,521			367,995
Municipal Loans	375,934			383,960			366,906			357,028			343,026
Loans to Individuals	98,439			100,005			100,949			100,708			100,102
Total Loans	$	3,601,002		$	3,568,204		$	3,499,917		$	3,460,143		$	3,305,110
Summary of Changes in Allowances:
Allowance for Loan Losses
Balance at beginning of period	$	24,797		$	25,129		$	24,705		$	24,155		$	27,019
Impact of CECL adoption (1) - cumulative effect adjustment	5,072			—			—			—			—
Impact of CECL adoption - purchased loans with credit deterioration	231			—			—			—			—
Loans charged-off	(995		)	(3,251		)	(1,000		)	(2,397		)	(2,285		)
Recoveries of loans charged-off	451			411			419			441			339
Net loans (charged-off) recovered	(544		)	(2,840		)	(581		)	(1,956		)	(1,946		)
Provision (reversal) for loan losses	24,082			2,508			1,005			2,506			(918		)
Balance at end of period	$	53,638		$	24,797		$	25,129		$	24,705		$	24,155
Allowance for Off-Balance-Sheet Credit Exposures
Balance at beginning of period	$	1,455		$	1,540		$	1,859		$	1,834		$	1,890
Impact of CECL adoption (1)	4,840			—			—			—			—
Provision (reversal) for off-balance-sheet credit exposures (2)	1,165			(85		)	(319		)	25			(56		)
Balance at end of period	$	7,460		$	1,455		$	1,540		$	1,859		$	1,834
Total Allowance for Credit Losses	$	61,098		$	26,252		$	26,669		$	26,564		$	25,989

(1) We adopted ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” on January 1, 2020. ASU 2016-13 replaced the incurred loss model with an expected loss methodology that is referred to as current expected credit losses (“CECL”). Adoption of this guidance on January 1, 2020, resulted in a cumulative-effect adjustment to reduce retained earnings by $7.8 million, net of tax.

(2) Prior to the adoption of CECL on January 1, 2020, the provision for off-balance-sheet credit exposures was included in other noninterest expense.

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Southside Bancshares, Inc.

Average Balances and Average Yields and Rates (Annualized) (Unaudited)

(Dollars in thousands)

The tables that follow show average earning assets and interest bearing liabilities together with the average yield on the earning assets and the average rate of the interest bearing liabilities for the periods presented. The interest and related yields presented are on a fully taxable-equivalent basis and are therefore non-GAAP measures. See “Non-GAAP Financial Measures” and “Non-GAAP Reconciliation” for more information.

	Three Months Ended
	March 31, 2020							December 31, 2019
	Average Balance			Interest		Average Yield/Rate		Average Balance			Interest		Average Yield/Rate
ASSETS
Loans (1)	$	3,587,143		$	42,554	4.77	%	$	3,540,274		$	43,166	4.84	%
Loans held for sale	831			9		4.36	%	1,114			9		3.21	%
Securities:
Taxable investment securities (2)	70,293			512		2.93	%	10,083			86		3.38	%
Tax-exempt investment securities (2)	888,906			7,837		3.55	%	699,868			6,431		3.65	%
Mortgage-backed and related securities (2)	1,598,374			11,534		2.90	%	1,674,503			12,197		2.89	%
Total securities	2,557,573			19,883		3.13	%	2,384,454			18,714		3.11	%
Federal Home Loan Bank stock, at cost, and equity investments	62,976			425		2.71	%	59,743			437		2.90	%
Interest earning deposits	40,236			180		1.80	%	44,039			247		2.23	%
Federal funds sold	—			—		—		—			—		—
Total earning assets	6,248,759			63,051		4.06	%	6,029,624			62,573		4.12	%
Cash and due from banks	76,739							72,018
Accrued interest and other assets	611,017							574,124
Less:  Allowance for loan losses	(30,373		)					(25,618		)
Total assets	$	6,906,142						$	6,650,148
LIABILITIES AND SHAREHOLDERS’ EQUITY
Savings accounts	$	384,863		237		0.25	%	$	372,798		262		0.28	%
Certificates of deposits	1,362,427			6,346		1.87	%	1,204,392			6,172		2.03	%
Interest bearing demand accounts	1,975,837			3,336		0.68	%	1,936,969			4,067		0.83	%
Total interest bearing deposits	3,723,127			9,919		1.07	%	3,514,159			10,501		1.19	%
Federal Home Loan Bank borrowings	999,070			3,974		1.60	%	1,019,844			4,716		1.83	%
Subordinated notes, net of unamortized debt issuance costs	98,597			1,411		5.76	%	98,554			1,426		5.74	%
Trust preferred subordinated debentures, net of unamortized debt issuance costs	60,234			600		4.01	%	60,250			643		4.23	%
Other borrowings	69,846			147		0.85	%	17,874			71		1.58	%
Total interest bearing liabilities	4,950,874			16,051		1.30	%	4,710,681			17,357		1.46	%
Noninterest bearing deposits	1,042,341							1,049,211
Accrued expenses and other liabilities	88,168							73,408
Total liabilities	6,081,383							5,833,300
Shareholders’ equity	824,759							816,848
Total liabilities and shareholders’ equity	$	6,906,142						$	6,650,148
Net interest income (FTE)				$	47,000						$	45,216
Net interest margin (FTE)						3.03	%						2.98	%
Net interest spread (FTE)						2.76	%						2.66	%

(1) Interest on loans includes net fees on loans that are not material in amount.

(2) For the purpose of calculating the average yield, the average balance of securities is presented at historical cost.

Note: As of March 31, 2020 and December 31, 2019, loans totaling $5.2 million and $5.0 million, respectively, were on nonaccrual status. Our policy is to reverse previously accrued but unpaid interest on nonaccrual loans; thereafter, interest income is recorded to the extent received when appropriate.

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Southside Bancshares, Inc.

Average Balances and Average Yields and Rates (Annualized) (Unaudited)

(Dollars in thousands)

	Three Months Ended
	September 30, 2019							June 30, 2019
	Average Balance			Interest		Average Yield/Rate		Average Balance			Interest		Average Yield/Rate
ASSETS
Loans (1)	$	3,477,187		$	43,780	5.00	%	$	3,387,323		$	43,559	5.16	%
Loans held for sale	2,497			26		4.13	%	1,965			21		4.29	%
Securities:
Taxable investment securities (2)	3,000			26		3.44	%	3,000			27		3.61	%
Tax-exempt investment securities (2)	555,835			5,328		3.80	%	459,996			4,513		3.94	%
Mortgage-backed and related securities (2)	1,660,331			12,569		3.00	%	1,680,109			13,246		3.16	%
Total securities	2,219,166			17,923		3.20	%	2,143,105			17,786		3.33	%
Federal Home Loan Bank stock, at cost, and equity investments	57,108			422		2.93	%	52,311			440		3.37	%
Interest earning deposits	26,746			206		3.06	%	66,017			411		2.50	%
Federal funds sold	—			—		—		3,365			39		4.65	%
Total earning assets	5,782,704			62,357		4.28	%	5,654,086			62,256		4.42	%
Cash and due from banks	73,815							78,757
Accrued interest and other assets	570,657							534,835
Less:  Allowance for loan losses	(24,938		)					(24,838		)
Total assets	$	6,402,238						$	6,242,840
LIABILITIES AND SHAREHOLDERS’ EQUITY
Savings accounts	$	367,615		270		0.29	%	$	365,205		262		0.29	%
Certificates of deposit	1,118,410			6,011		2.13	%	1,119,464			5,861		2.10	%
Interest bearing demand accounts	1,966,764			5,085		1.03	%	1,969,593			5,334		1.09	%
Total interest bearing deposits	3,452,789			11,366		1.31	%	3,454,262			11,457		1.33	%
Federal Home Loan Bank borrowings	881,088			4,647		2.09	%	755,748			3,899		2.07	%
Subordinated notes, net of unamortized debt issuance costs	98,511			1,425		5.74	%	98,469			1,410		5.74	%
Trust preferred subordinated debentures, net of unamortized debt issuance costs	60,248			685		4.51	%	60,247			718		4.78	%
Other borrowings	13,401			59		1.75	%	14,530			57		1.57	%
Total interest bearing liabilities	4,506,037			18,182		1.60	%	4,383,256			17,541		1.61	%
Noninterest bearing deposits	1,020,325							1,014,746
Accrued expenses and other liabilities	72,923							73,494
Total liabilities	5,599,285							5,471,496
Shareholders’ equity	802,953							771,344
Total liabilities and shareholders’ equity	$	6,402,238						$	6,242,840
Net interest income (FTE)				$	44,175						$	44,715
Net interest margin (FTE)						3.03	%						3.17	%
Net interest spread (FTE)						2.68	%						2.81	%

(1) Interest on loans includes net fees on loans that are not material in amount.

(2) For the purpose of calculating the average yield, the average balance of securities is presented at historical cost.

Note: As of September 30, 2019 and June 30, 2019, loans totaling $17.1 million and $16.4 million, respectively, were on nonaccrual status. Our policy is to reverse previously accrued but unpaid interest on nonaccrual loans; thereafter, interest income is recorded to the extent received when appropriate.

Page-11

Southside Bancshares, Inc.

Average Balances and Average Yields and Rates (Annualized) (Unaudited)

(Dollars in thousands)

	Three Months Ended
	March 31, 2019
	Average Balance			Interest		Average Yield/Rate
ASSETS
Loans (1)	$	3,296,665		$	42,210	5.19	%
Loans held for sale	611			7		4.65	%
Securities:
Taxable investment securities (2)	3,000			28		3.79	%
Tax-exempt investment securities (2)	659,187			5,732		3.53	%
Mortgage-backed and related securities (2)	1,647,564			12,474		3.07	%
Total securities	2,309,751			18,234		3.20	%
Federal Home Loan Bank stock, at cost, and equity investments	53,764			355		2.68	%
Interest earning deposits	64,690			386		2.42	%
Federal funds sold	7,635			47		2.50	%
Total earning assets	5,733,116			61,239		4.33	%
Cash and due from banks	83,147
Accrued interest and other assets	513,738
Less:  Allowance for loan losses	(27,060		)
Total assets	$	6,302,941
LIABILITIES AND SHAREHOLDERS’ EQUITY
Savings accounts	$	360,664		258		0.29	%
Certificates of deposit	1,154,203			5,697		2.00	%
Interest bearing demand accounts	1,982,891			5,286		1.08	%
Total interest bearing deposits	3,497,758			11,241		1.30	%
Federal Home Loan Bank borrowings	816,389			4,457		2.21	%
Subordinated notes, net of unamortized debt issuance costs	98,428			1,400		5.77	%
Trust preferred subordinated debentures, net of unamortized debt issuance costs	60,246			729		4.91	%
Other borrowings	16,788			75		1.81	%
Total interest bearing liabilities	4,489,609			17,902		1.62	%
Noninterest bearing deposits	986,343
Accrued expenses and other liabilities	89,768
Total liabilities	5,565,720
Shareholders’ equity	737,221
Total liabilities and shareholders’ equity	$	6,302,941
Net interest income (FTE)				$	43,337
Net interest margin (FTE)						3.07	%
Net interest spread (FTE)						2.71	%

(1) Interest on loans includes net fees on loans that are not material in amount.

(2) For the purpose of calculating the average yield, the average balance of securities is presented at historical cost.

Note: As of March 31, 2019, loans totaling $17.7 million were on nonaccrual status. Our policy is to reverse previously accrued but unpaid interest on nonaccrual loans; thereafter, interest income is recorded to the extent received when appropriate.

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Southside Bancshares, Inc.

Non-GAAP Reconciliation (Unaudited)

(Dollars and shares in thousands, except per share data)

The following tables set forth the reconciliation of return on average common equity to return on average tangible common equity, book value per share to tangible book value per share, net interest income to net interest income adjusted to a fully taxable-equivalent basis assuming a 21% marginal tax rate for interest earned on tax-exempt assets such as municipal loans and investment securities, along with the calculation of total revenue, adjusted noninterest expense, efficiency ratio (FTE), net interest margin (FTE) and net interest spread (FTE) for the applicable periods presented.

	Three Months Ended
	2020			2019
	Mar 31,			Dec 31,			Sep 30,			Jun 30,			Mar 31,
Reconciliation of return on average common equity to return on average tangible common equity:
Net income	$	3,953		$	17,335		$	19,792		$	18,610		$	18,817
After-tax amortization expense	774			814			853			892			931
Adjusted net income available to common shareholders	$	4,727		$	18,149		$	20,645		$	19,502		$	19,748
Average shareholders' equity	$	824,759		$	816,848		$	802,953		$	771,344		$	737,221
Less: Average intangibles for the period	(214,104		)	(215,101		)	(216,169		)	(217,266		)	(218,438		)
Average tangible shareholders' equity	$	610,655		$	601,747		$	586,784		$	554,078		$	518,783
Return on average tangible common equity	3.11		%	11.97		%	13.96		%	14.12		%	15.44		%
Reconciliation of book value per share to tangible book value per share:
Common equity at end of period	$	795,800		$	804,580		$	810,453		$	787,765		$	758,033
Less: Intangible assets at end of period	(213,497		)	(214,477		)	(215,507		)	(216,587		)	(217,716		)
Tangible common shareholders' equity at end of period	$	582,303		$	590,103		$	594,946		$	571,178		$	540,317
Total assets at end of period	$	7,273,638		$	6,748,913		$	6,542,075		$	6,372,870		$	6,217,196
Less: Intangible assets at end of period	(213,497		)	(214,477		)	(215,507		)	(216,587		)	(217,716		)
Tangible assets at end of period	$	7,060,141		$	6,534,436		$	6,326,568		$	6,156,283		$	5,999,480
Period end tangible equity to period end tangible assets	8.25		%	9.03		%	9.40		%	9.28		%	9.01		%
Common shares outstanding end of period	33,012			33,823			33,795			33,749			33,718
Tangible book value per common share	$	17.64		$	17.45		$	17.60		$	16.92		$	16.02
Reconciliation of efficiency ratio to efficiency ratio (FTE), net interest margin to net interest margin (FTE) and net interest spread to net interest spread (FTE):
Net interest income (GAAP)	$	44,701		$	43,176		$	42,373		$	43,131		$	41,125
Tax equivalent adjustments:
Loans	668			653			641			598			598
Tax-exempt investment securities	1,631			1,387			1,161			986			1,614
Net interest income (FTE) (1)	47,000			45,216			44,175			44,715			43,337
Noninterest income	15,498			10,465			11,111			11,254			9,538
Nonrecurring income (2)	(5,541		)	(42		)	(42		)	(557		)	171
Total revenue	$	56,957		$	55,639		$	55,244		$	55,412		$	53,046
Noninterest expense	$	30,520		$	30,944		$	29,026		$	29,700		$	29,627
Pre-tax amortization expense	(980		)	(1,030		)	(1,080		)	(1,129		)	(1,179		)
Nonrecurring expense (3)	29			56			(33		)	(67		)	18
Adjusted noninterest expense	$	29,569		$	29,970		$	27,913		$	28,504		$	28,466
Efficiency ratio	54.10		%	55.92		%	52.23		%	52.95		%	56.00		%
Efficiency ratio (FTE) (1)	51.91		%	53.87		%	50.53		%	51.44		%	53.66		%
Average earning assets	$	6,248,759		$	6,029,624		$	5,782,704		$	5,654,086		$	5,733,116
Net interest margin	2.88		%	2.84		%	2.91		%	3.06		%	2.91		%
Net interest margin (FTE) (1)	3.03		%	2.98		%	3.03		%	3.17		%	3.07		%
Net interest spread	2.61		%	2.52		%	2.55		%	2.69		%	2.56		%
Net interest spread (FTE) (1)	2.76		%	2.66		%	2.68		%	2.81		%	2.71		%

(1) These amounts are presented on a fully taxable-equivalent basis and are non-GAAP measures.

(2) These adjustments may include net gain and loss on sale of securities available for sale and loss on fair value hedges, in the periods where applicable.

(3) These adjustments may include foreclosure expenses, in the periods where applicable.

Page-13