Financial Highlights: 1st Quarter 2024

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Forward-looking statements and additional information

Statements in this presentation which are not historical are "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, Section 21E of the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995. These forward-looking statements may include discussions of the strategic plans and objectives or anticipated future performance and results of MainStreet Bancshares, Inc. or MainStreet Bank (the "Company").

The information contained in this presentation should be read in conjunction with the Company's most recent Form 10-K and all subsequent Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, each of which is available on the Securities and Exchange Commission's ("SEC") website (sec.gov).

Investors are cautioned that forward-looking statements, which are not historical fact, involve risks, assumptions and uncertainties that change

over time, including those detailed in Form 10-K under the section, "Risk Factors".

As such, actual results could differ materially from those expressed or implied by forward- looking statements made in this presentation. Management believes that the expectations in these forward-looking statements are based upon reasonable assumptions within the bounds of management's current knowledge of the Company's business and operations. The Company disclaims any responsibility to update these forward-looking statements to reflect events or circumstances after the date of this presentation.

The accounting and reporting policies of the Company conform to U.S. Generally Accepted Accounting Principles (GAAP) and prevailing practices in the banking industry. However, certain non-GAAP measures are used by management to supplement the evaluation of the Company's performance.

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Much has been written of late about the banks that offered Banking-as-a-Service through intermediaries…

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Banking-as-a-service banks: 'There is a reckoning'

By Miriam Cross. February 7, 2024

The quickening waves of consent orders slamming into financial institutions engaged in banking-as-a- service is spurring change among banks who want to get it right.

Banks are ultimately responsible for the deposit, lending and credit activity their partners engage in. There are also growing concerns about the reliability of third parties that connect banks to fintechs and their promises to offload some of the compliance burden.

At the same time, crackdowns on banks partaking in BaaS are on the rise. Financial institutions have been forced by regulators to heighten oversight of their fintech partners, strengthen compliance and more.

"Financial institutions have been forced by regulators to heighten oversight of their fintech partners, strengthen compliance and more."

Excerpts from: Cross, Miriam (2-7-2024), Banking-as-a-service banks: 'There is a reckoning', American Banker

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Small group of banking-as-a-service banks logs big number of enforcement actions

Author Yizhu Wang, Thomas Mason

US banks with financial technology partnerships accounted for an outsized share of severe enforcement actions in 2023. In 2023, banks that provide banking as a service (BaaS) to fintech partners accounted for 13.5% of severe enforcement actions issued by federal bank regulators, including prompt corrective action directives, cease and desist orders, consent orders and formal agreements, according to data compiled by S&P Global Market Intelligence.

The number of banks that received enforcement actions due to fintech partnerships is disproportionately large, considering it is estimated that fewer than 100 community banks are in the business of BaaS and there are roughly 4,800 banks in the US.

"US banks with

financial technology

partnerships

accounted for an outsized share of severe enforcement actions in 2023."

Excerpts from: Wang, Yizhu & Mason, Thomas, (1-22-2024), Small group of banking-as-a-service banks logs big number of enforcement actions, S&P Global Market Intelligence

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Regulatory scrutiny will likely separate committed banks..."

Excerpts from: Hrushka, Anna (1-22-24) BaaS to require strong commitment, investment in 2024, experts say, Banking Dive Financial Analytics

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Where Is Banking-As-A-Service Headed In 2024?

Kate Drew

Contributor

When looking toward the future of the fintech industry in 2024, one of the most salient questions is what developments we may see in Banking-as-a-Service, or BaaS.

The truth is many of the most jarring headlines have involved sponsor banks and fintech partners that had little to no relationship at all, and instead operated through a BaaS provider (like Synapse) that served as a middleman with the goal of streamlining the process of getting things up and running.

That model is all but dead. In its place will likely emerge a more resilient BaaS proposition that puts the bank in the driver's seat when it comes to compliance and focuses on fintechs (or other nonbanks) with sustainable businesses and realistic objectives in financial services.

"That

model is all but dead."

Excerpts from: Drew, Kate (12-12-2023),Where is Banking-as-aService Headed in 2024? Forbes Media L.L.C.

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We believe the opportunities are boundless for banks that provide Banking-as-a-Service in a responsible way

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We've said it from the start

What 6 years of providing Banking as a Service taught us

We need our own:

• Distributed Ledger
• Integrated CIP, KYC, BSA & AML technology
• Integrated Compliance & Complaint Management
• Integrated Monitoring Systems
• Leading Edge Cybersecurity systems
• Compliance & Marketing Training Program

Excerpts from our presentation to the Fed in May 2021

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