Main Street Capital : 2024 Analysts’ and Investors’ Day

Analysts' and Investors' Day

June 2024

Main StreetCapital Corporation	NYSE: MAIN	mainstcapital.com.com
Main	Corp	NYSE:

Disclaimers

Main Street Capital Corporation (MAIN) cautions that statements in this presentation that are forward-looking, and provide other than historical information, involve risks and uncertainties that may impact our future results of operations. The forward-looking statements in this presentation are based on current conditions as of June 19, 2024, and include, but are not limited to, statements regarding our goals, beliefs, strategies, future operating results and cash flows, operating expenses, investment originations and performance, available capital, payment and the tax attributes of future dividends and shareholder returns. Although our management believes that the expectations reflected in any forward-looking statements are reasonable, we can give no assurance that those expectations will prove to have been correct. Those statements are made based on various underlying assumptions and are subject to numerous uncertainties and risks, including, without limitation: our continued effectiveness in raising, investing and managing capital; adverse changes in the economy generally or in the industries in which our portfolio companies operate; the impacts of macroeconomic factors on MAIN and its portfolio companies' business and operations, liquidity and access to capital, and on the U.S. and global economies, including impacts related to pandemics and other public health crises, risk of recession, inflation, supply chain constraints or disruptions and changes in market index interest rates; changes in laws and regulations or business, political and/or regulatory conditions that may adversely impact our operations or the operations of our portfolio companies; the operating and financial performance of our portfolio companies and their access to capital; retention of key investment personnel; competitive factors; and such other factors described under the captions "Cautionary Statement Concerning Forward- Looking Statements," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and "Risk Factors" included in our filings with the Securities and Exchange Commission (the SEC)(www.sec.gov), including our most recent annual report on Form 10-K and subsequently filed quarterly reports on Form 10-Q. We undertake no obligation to update the information contained herein to reflect subsequently occurring events or circumstances, except as required by applicable securities laws and regulations.

The preliminary estimates of second quarter 2024 financial information and results furnished in this presentation are based on MAIN management's preliminary determinations and current expectations, and such information is inherently uncertain. The preliminary estimates are subject to completion of MAIN's customary quarter-end closing and review procedures and third-party review,

including the determination of the fair value of MAIN's portfolio investments. As a result, actual results could differ materially from the current preliminary estimates based on adjustments made during MAIN's quarter-end closing and review procedures and third-party review, and MAIN's reported information in its Quarterly Report on Form 10-Q for the quarter ended June 30, 2024 may differ from this information, and any such differences may be material. In addition, the information furnished above does not include all of the information regarding MAIN's financial condition and results of operations for the quarter ended June 30, 2024 that may be important to readers. As a result, readers are cautioned not to place undue reliance on the information furnished in this presentation and should view this information in the context of MAIN's full second quarter 2024 results when such results are disclosed by MAIN in its Quarterly Report on Form 10-Q for the quarter ended June 30, 2024.

MAIN has filed a registration statement (which includes a prospectus) with the SEC for any offering to which this communication may relate and may file one or more supplements to the prospectus in the future.

MAIN is classified as a non-diversified investment company within the meaning of the 1940 Act, which means that it is not limited by the 1940 Act with respect to the proportion of its assets that it may invest in securities of a single issuer. Before you invest in any of MAIN's securities, you should read the registration statement, the prospectus and the applicable prospectus supplement(s) in order to fully understand all of the implications and risks of an offering of MAIN's securities. You should also read other documents MAIN has filed with the SEC for more complete information about MAIN and its securities offerings. You may access these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, MAIN will arrange to send you any applicable prospectus and prospectus supplement if you request such materials by calling us at [phone]. These materials are also made available, free of charge, on our website at www.mainstcapital.com. Information contained on our website is not incorporated by reference into this communication.

The summary descriptions and other information included herein are intended only for informational purposes and convenient reference. The information contained herein is not intended to provide, and should not be relied upon for, accounting, legal or tax advice or investment recommendations. Before making an investment decision with respect to MAIN, investors are advised consult with their tax, financial, investment and legal advisors.

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

A Differentiated Approach

Focus on Lower Middle Market debt and equity investment strategy and internally managed operating structure differentiates MAIN from other investment firms

Attractive and growing Asset Management Business, primarily driven by strong direct lending capabilities, provides further differentiation

Primarily Invests in the under-served Lower Middle Market (LMM)

• Targets companies with revenue between $10 million - $150 million; EBITDA between $3 million - $20 million

Equity investments are key component of LMM portfolio

• Key contributor to our 130% growth (5.3% CAGR) in net asset value (NAV) per share since 2007 through March 31, 2024
• Generate dividend income and realized gains to support dividend growth

Internally-managed operating structure

• Alignment of interests between MAIN management and our shareholders
• Provides cost efficient model with significant operating leverage

Attractive asset management advisory business Significant management ownership / investment in MAIN

Strong capitalization and liquidity position - stable, long-term debt and significant available liquidity to take advantage of future opportunities

• Favorable opportunities in capital markets through investment grade ratings of BBB-/Stable from Fitch Ratings and BBB-/Stable from Standard & Poor's Global Ratings
• Total liquidity in excess of $1 billion as of June 19, 2024(1)

(1) Includes cash and undrawn portion of debt capital as of June 19, 2024

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Investment Strategy

LMM investment strategy differentiates MAIN from its competitors and provides attractive risk-adjusted returns

MAIN's permanent capital structure as a publicly traded investment firm allows MAIN to maintain a long-term to permanent expected holding period for its LMM investments, providing significant benefits to both MAIN and our LMM portfolio companies

Investment Objectives

• High cash yield from secured debt investments (12.5% weighted- average cash coupon as of March 31, 2024); plus
• Dividend income, fair value appreciation and periodic capital gains from equity investments

Investments are structured for (i) protection of capital, (ii) high recurring income and (iii) meaningful capital gain opportunity

Focus on self-sponsored, "one stop" financing opportunities

• Partner with business owners, management teams and entrepreneurs
• Provide highly customized financing solutions
• Recapitalization, buyout, growth and acquisition capital
• Extensive network of grass roots referral sources
• Strong and growing "Main Street" brand recognition / reputation

Investments have low correlation to the broader debt and equity markets and attractive risk-adjusted returns

Unique LMM strategy, combined with MAIN's perpetual capital structure and goal to be long-term partners, results in a highly diversified and high-quality investment portfolio

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Investment Opportunity

MAIN targets LMM investments in established, profitable companies

Characteristics of LMM provide beneficial risk- reward investment opportunities

Large and critical portion of U.S. economy

• 195,000+ domestic LMM businesses(1)

LMM is under-served from a capital perspective and less competitive

Inefficient asset class generates pricing inefficiencies

• Typical entry enterprise values between 4.5X - 6.5X EBITDA
• Typical entry leverage multiples between 2.0X - 4.0X EBITDA to MAIN debt investment

Partner relationship with the management teams of our portfolio companies vs. a "commoditized vendor of capital"

1. Source: U.S. Census 2017 - U.S. Data Table by Enterprise Receipt Size; 2017 County Business Patterns and 2017 Economic Census; includes Number of Firms with Enterprise Receipt Size between $10,000,000 and $99,999,999

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Investment Portfolio(1)

LMM investment portfolio consists of a diversified mix of secured debt and lower cost basis equity investments

MAIN's long-term to permanent expected holding period for its LMM investments enhances the diversity and quality of its LMM investment portfolio

1. As of March 31, 2024

81 portfolio companies / $2.4 billion in fair value

• 53% of total investment portfolio(2) at fair value

Debt yielding 12.8%(3) (73% of LMM portfolio at cost)

• Over 99% of debt investments have first lien position
• 72% of debt investments earn fixed-rate interest
• Over 840 basis point net cash interest margin vs "matched" fixed interest rate on SBIC debentures and Notes Payable

Equity ownership in all LMM portfolio companies representing 40% average ownership position (27% of LMM portfolio at cost)

• Lower entry multiple valuations, lower cost basis
• Opportunity for dividend income, fair value appreciation and periodic capital gains
• 63% of LMM companies(4) with direct equity investment are currently paying dividends
• Fair value appreciation of equity investments supports Net Asset Value per share growth
• $511.2 million, or $6.00 per share, of cumulative pre-tax net unrealized appreciation at March 31, 2024

1. Excludes $103.4 million of fair value of short-term portfolio investments as described in MAIN's SEC filings, as these investments are deemed to be short-term in nature, as opposed to a long-term component of MAIN's investment portfolio
2. Weighted-averageeffective yield is calculated using the applicable interest rate as of March 31, 2024 and includes amortization of deferred debt origination fees and accretion of original issue discount, but excludes fees payable upon repayment of the debt instruments and any debt investments on non-accrual status
3. Includes the LMM companies that (a) MAIN has a direct equity investment and (b) are flow-through entities for tax purposes; based upon dividend income for the trailing twelve- month period ended March 31, 2024

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Investment Portfolio(1)

LMM investment portfolio is a pool of high quality, seasoned assets with attractive risk-adjusted return characteristics

MAIN's long-term to permanent expected holding period for its LMM investments significantly enhances the quality of MAIN's LMM investment portfolio and drives significant fair value appreciation

Median LMM portfolio credit statistics(2):

• Senior leverage of 3.0x EBITDA through MAIN debt position
• 2.4x EBITDA to senior interest coverage
• Total leverage of 3.0x EBITDA including debt junior in priority to MAIN
• Free cash flow de-leveraging improves credit metrics and increases equity appreciation

Average investment size of $29.2 million at fair value or

$22.8 million on a cost basis (less than 1% of total investment portfolio)

Opportunistic, selective posture toward new investment activity over the economic cycle

High quality, seasoned LMM portfolio

• MAIN has been invested in 27% (22 different companies) of its LMM portfolio companies for greater than 10 years (representing 9% of total costs basis and 14% of total fair value)
• Total LMM investment portfolio at fair value equals 128% of cost
• Equity component of LMM portfolio at fair value equals 206% of cost
• Majority of LMM portfolio companies have de-leveraged and experienced equity appreciation
• • 49 LMM portfolio companies with unrealized appreciation on equity investments
  • Net unrealized appreciation on LMM equity investments of $536.6 million

1. As of March 31, 2024
2. These credit statistics exclude portfolio companies on non-accrual and five companies for which EBITDA is not a meaningful metric

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Portfolio by Industry (as a Percentage of Cost)(1)

1. As of March 31, 2024

Main Street Capital Corporation

NYSE: MAIN

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Diversified LMM Portfolio (as a Percentage of Cost)(1)

Invested Capital by Transaction Type

LBO/MBO	Recapitalization/
	Refinancing
Acquisition
	Growth Capital

Invested Capital by Geography(2)

23%

25%

16%

25% 11%

1. As of March 31, 2024
2. Based upon portfolio company headquarters

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com

LMM Investments are Purchased at Attractive Valuations

MAIN maintains a value orientation towards LMM investments

• MAIN's unique approach to the LMM and the limited competition in the LMM allows MAIN to consistently invest in LMM companies at attractive valuations relative to the broader private equity universe
• Lower equity cost basis increases the likelihood and opportunity for significant capital gains upon exit
• Reasonable entry valuations and materially lower leverage levels reduce the risk of credit deterioration due to excessive leverage

Purchase Multiple Comparison:

MAIN LMM versus Broader Middle-Market Private Equity

Multiple

16x

14x

13.4x

13.8x

12.8x

13.6x

Purchase

11.9x

12.6x

12x

11.1x

11.1x

10.8x

EBITDA/

10x

8x

(EV)

6.3x

6.0x

6.5x

6.3x

6.2x

6.1x

6.0x

6.0x

6.0x

6x

Value

4x

Enterprise

2x

0x

2015

2016

2017

2018

2019

2020

2021

2022

2023

Median Middle-Market Private Equity Multiple(1)

MAIN Weighted Average LMM Purchase Multiple (2)

1. Represents the median purchase price multiple (EV / EBITDA) for middle-market private equity buyouts occurring during the period presented; Source: PitchBook 2023 US Middle Market Report
2. Represents the weighted average purchase price (EV / EBITDA) multiple for MAIN LMM transactions that closed during the year presented; the calculation is weighted by the amount of debt and equity capital initially invested by MAIN; of the 65 new platform LMM investments completed from 2015 through 2023, 6 are excluded from the analysis above: 4 transactions for which an EBITDA multiple was not relevant to the transaction's entry valuation, and 2 transactions that are considered non-recurring and unique in nature whose EBITDA multiples represent outliers from the typical LMM entry multiple target

Main Street Capital Corporation

NYSE: MAIN

mainstcapital.com