S&T Bancorp : 1Q24 Investor Presentation

First Quarter 2024

Christopher J. McComish

Chief Executive Officer

Mark Kochvar

Chief Financial Officer

Forward Looking Statements and Risk Factors

This information contains or incorporates statements that we believe are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements generally relate to our financial condition, results of operations, plans, objectives, outlook for earnings, revenues, expenses, capital and liquidity levels and ratios, asset levels, asset quality, financial position and other matters regarding or affecting S&T and its future business and operations. Forward-looking statements are typically identified by words or phrases such as "will likely result," "expect," "anticipate," "estimate," "forecast," "project," "intend," "believe," "assume," "strategy," "trend," "plan," "outlook," "outcome," "continue," "remain," "potential," "opportunity," "comfortable," "current," "position," "maintain," "sustain," "seek," "achieve" and variations of such words and similar expressions, or future or conditional verbs such as will, would, should, could or may. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. The matters discussed in these forward-looking statements are subject to various risks, uncertainties and other factors that could cause actual results and trends to differ materially from those made, projected or implied in or by the forward-looking statements depending on a variety of uncertainties or other factors including, but not limited to: credit losses and the credit risk of our commercial and consumer loan products; changes in the level of charge-offs and changes in estimates of the adequacy of the allowance for credit losses, or ACL; cyber-security concerns; rapid technological developments and changes; operational risks or risk management failures by us or critical third parties, including fraud risk; our ability to manage our reputational risks; sensitivity to the interest rate environment, a rapid increase in interest rates or a change in the shape of the yield curve; a change in spreads on interest-earning assets and interest-bearing liabilities; any remaining uncertainties with the transition from LIBOR as a reference rate; regulatory supervision and oversight, including changes in regulatory capital requirements and our ability to address those requirements; unanticipated changes in our liquidity position; unanticipated changes in regulatory and governmental policies impacting interest rates and financial markets; changes in accounting policies, practices or guidance; legislation affecting the financial services industry as a whole, and S&T, in particular; developments affecting the industry and the soundness of financial institutions and further disruption to the economy and U.S. banking system; the outcome of pending and future litigation and governmental proceedings; increasing price and product/service competition; the ability to continue to introduce competitive new products and services on a timely, cost-effective basis; managing our internal growth and acquisitions; the possibility that the anticipated benefits from acquisitions cannot be fully realized in a timely manner or at all, or that integrating the acquired operations will be more difficult, disruptive or costly than anticipated; containing costs and expenses; reliance on significant customer relationships; an interruption or cessation of an important service by a third-party provider; our ability to attract and retain talented executives and employees; general economic or business conditions, including the strength of regional economic conditions in our market area; ESG practices and disclosures, including climate change, hiring practices, the diversity of the work force, and racial and social justice issues; deterioration of the housing market and reduced demand for mortgages; deterioration in the overall macroeconomic conditions or the state of the banking industry that could warrant further analysis of the carrying value of goodwill and could result in an adjustment to its carrying value resulting in a non-cash charge to net income; the stability of our core deposit base and access to contingency funding; re-emergence of turbulence in significant portions of the global financial and real estate markets that could impact our performance, both directly, by affecting our revenues and the value of our assets and liabilities, and indirectly, by affecting the economy generally and access to capital in the amounts, at the times and on the terms required to support our future businesses and geopolitical tensions and conflicts between nations.

Many of these factors, as well as other factors, are described in our Annual Report on Form 10-K for the year ended December 31, 2023, including Part I, Item 1A-"Risk Factors" and any of our subsequent filings with the SEC. Forward-looking statements are based on beliefs and assumptions using information available at the time the statements are made. We caution you not to unduly rely on forward-looking statements because the assumptions, beliefs, expectations and projections about future events may, and often do, differ materially from actual results. Any forward-looking statement speaks only as to the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect developments occurring after the statement is made.

Non-GAAP

Financial Measures

In addition to the traditional measures presented in accordance with Generally Accepted Accounting Principles (GAAP), S&T management uses and this presentation contains or references certain non-GAAP financial measures, such as net interest income on a fully taxable equivalent basis. S&T believes these non-GAAP financial measures provide information useful to investors in understanding our underlying business, operational performance and performance trends which facilitate comparisons with the performance of others in the financial services industry. Although S&T believes that these non-GAAP financial measures enhance investors' understanding of S&T's business and performance, these non-GAAP financial measures should not be considered an alternative to GAAP or considered to be more important than financial results determined in accordance with GAAP, nor are they necessarily comparable with non-GAAP measures which may be presented by other companies. The non-GAAP financial measures contained within this presentation should be read in conjunction with the audited financial statements and analysis as presented in the Annual Report on Form 10-K as well as the unaudited financial statements and analyses as presented in the respective Quarterly Reports in Exhibit 99.1 of Form 8-K for S&T Bancorp, Inc. and subsidiaries.

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Corporate Profile

• $9.5 billion in assets
• $7.6 billion in deposits
• $7.7 billion in loans
• $1.2 billion market cap
• Stock symbol: STBA

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Geographic	Serving more than
Footprint	225,000 customers
Ohio
	in Pennsylvania and

Akron

Indiana

Columbus

Pittsburgh

Footprint	1,200 team members
comprises	providing award-
9.6 million people	winning customer
and 215,000	satisfaction at 72
businesses	locations

Harrisburg

Philadelphia

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Awards

Forbes America's Best Banks

S&T was named on the Forbes list of America's Best Banks in 2024. This annual ranking is based on metrics measuring growth, credit quality and profitability, as well as stock performance.

Forbes America's Best Mid-Size

Employers

S&T was honored as one of America's Best Mid-Size Employers by Forbes and Statista in 2023 and 2024.

Forbes Best-In-State Banks

S&T was named on the Forbes list of Best-In-State Banks 2023 for the second consecutive year. Consumers assessed banks regarding overall satisfaction, trust, terms and conditions, branch services, digital services, customer service and financial advice.

Top Workplaces USA 2023

S&T was recognized as a top workplace in the United States, issued by Energage. We were chosen based solely on employee feedback.

Top Workplace for Work-Life Flexibility

S&T was awarded the 2023 Top Workplaces Culture Excellence award for Work-Life Flexibility, issued by Energage.

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Strategic Path Forward

"Our Shared Future"

VALUES

PURPOSE

DRIVERS

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Delivering long-term, sustainable financial performance

(measured by top quartile Price/TBV and Total Shareholder Return)

Unwavering focus on key Drivers of business performance and profitable growth

DEPOSIT FRANCHISE

Loans/Deposit Ratio, Cost of Deposits

• Treasury Management distribution and product capabilities
• Customer relationship management and sales effectiveness
• Product optimization
• Digital experience evolution

TALENT & ENGAGEMENT

Loyalty, Retention

• "Our Shared Future" culture and mindset
• Talent acquisition and retention
• Diversity, Equity & Inclusion
• Workday Human Resources management system

ASSET QUALITY

NCO/Loans, NPA/Loans & OREO

• Portfolio segmentation and concentration strategy
• Credit risk management practices
• Process & technology enhancements
• Specialized regional credit officer model

CORE PROFITABILITY

PPNR/Avg Assets, NIM

• NIM management
• Balance efficiency and infrastructure investments
• Centralized Data & Analytics to bolster strategic decision-making
• Small Business distribution expansion

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Positioned for Growth

We have been making meaningful and scalable investments in technology and people to prepare for future growth.

FINANCIAL

STRENGTH

• Strong capital levels to support both organic and inorganic growth
• Durbin Amendment impact approximately $7 million (2% of total revenue)
• Solid financial performance

TALENT

• Augmented legacy S&T leadership with team members having larger bank experience
• • Senior Leadership Team - 7 of 16 have prior experience at $25 billion + banks
  • Risk Management Team - 6 of 12 in leadership roles have prior experience at $25 billion + banks

REGULATORY

COMPLIANCE

• Enhanced governance structure
• Integrated, Enterprise Risk Management Program
• Strengthened Credit Administration practices
• Advanced Consumer Compliance Infrastructure

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First Quarter Overview

HIGHLIGHTS

• Solid earnings and return metrics
• NIM remains strong at 3.84%
• Third consecutive quarter of customer deposit growth
• Healthy ACL level with manageable NPAs
• Forbes 2024 America's Best Banks
• Forbes 2024 list of America's Best Midsize Employers

EARNINGS

RETURN METRICS

BALANCE SHEET

ASSET QUALITY

EPS	Net Income
$0.81	$31.2 million

ROA	ROE	NIM*
1.32%	9.74%	3.84%
ROTE*	PPNR*	Efficiency
Ratio*
13.85%	1.76%
56.21%

Loan growth	Deposit growth
$2.7 million	$78.6 million
0.14% (annualized)	4.21% (annualized)

ACL NCO NPA

1.37% 0.35% 0.44%

*Refer to appendix for reconciliation of non-GAAP financial measures

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Performance

RETURN ON AVERAGE ASSETS

RETURN ON AVERAGE EQUITY

1.6%			1.48%	1.56%		15.0%
					1.32%			11.47%	11.80%
1.2%		1.18%
1.32%								9.74%
				10.0%	9.30%
					Peer(2*)
0.8%	0.74%(1*)								Peer(2*)
				5.76%(1*)
0.4%						5.0%
	0.23%					1.80%
0.0%	2020	2021	2022	2023	1Q24	0.0%	2021	2022	2023	1Q24
	2020

RETURN ON AVERAGE TANGIBLE EQUITY *

PPNR / AVERAGE ASSETS *

20.0%			17.02%	17.15%		2.4%				2.12%
							1.93%
15.0%		13.85%			13.85%	1.8%	1.67%	1.62%			1.76%
	14.41%				Peer(2*)
10.0%	8.80%(1*)					1.2%					Peer(2*)
5.0%						0.6%
	2.92%
0.0%	2020	2021	2022	2023	1Q24	0.0%	2020	2021	2022	2023	1Q24

(1)This is a non-GAAP number that adjusts for a pre-tax loss of $58.7 million resulting from customer fraud related to a check kiting scheme in Q2 2020.

1. Median of proxy peer group. Peer data from S&P Global Market Intelligence. .

(*)Refer to appendix for reconciliation of non-GAAP financial measures.

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