Wed, November 03, 2021

Q3 2021 Earnings Presentation

November 4, 2021

Important Notices and Safe Harbor Statement

This presentation contains forward looking statements, which are not guarantees of future performance, conditions or results, and involve substantial risks and uncertainties, including the impact of COVID-19 and related changes in base interest rates and significant volatility on our business, portfolio companies, our industry, and the global economy. All forward-looking statements included in this presentation are made only as of the date hereof and are subject to change without notice. Actual outcomes and results could differ materially from those suggested by this presentation due to the impact of many factors beyond the control of New Mountain Finance Corporation ("NMFC"), including those listed in the "Risk Factors" section of our filings with the United States Securities and Exchange Commission ("SEC"). Any such forward-looking statements are made pursuant to the safe harbor provisions available under applicable securities laws and NMFC assumes no obligation to update or revise any such forward-looking statements unless required by law. Certain information discussed in this presentation (including information relating to portfolio companies) was derived from third party sources and has not been independently verified and, accordingly, NMFC makes no representation or warranty with respect to this information.

The following slides contain summaries of certain financial and statistical information about NMFC. The information contained in this presentation is summary information that is intended to be considered in the context of our SEC filings and other public announcements that we may make, by press release or otherwise, from time to time. We undertake no duty or obligation to publicly update or revise the information contained in this presentation unless required by law. In addition, information related to past performance, while helpful as an evaluative tool, is not necessarily indicative of future results, the achievement of which cannot be assured. You should not view the past performance of NMFC, or information about the market, as indicative of NMFC's future results. The performance data stated herein may have been due to extraordinary market conditions, which may not be duplicated in the future. Current performance may be lower or higher than the performance data quoted. This presentation does not constitute an offer to sell or the solicitation of an offer to buy any securities of NMFC.

Past performance is not indicative nor a guarantee of future returns, the realization of which is dependent on many factors, many of which are beyond the control of NMFC. There can be no assurances that future dividends will match or exceed historic ones, or that they will be made at all. Net returns give effect to all fees and expenses. Unless otherwise noted, information included herein is presented as of the date indicated on the cover page and may change at any time without notice. NMFC is subject to certain significant risks relating to our business and investment objective. For more detailed information on risks relating to NMFC, see the latest Form 10-K and subsequent quarterly reports filed on Form 10-Q.

Investment portfolio related activity, metrics and disclosures on slides 7, 12, 13, 17, 18, 24, 25, 26, 27, 28, 30, 31, and 38 include the underlying collateral from securities purchased under collateralized agreements to resell and exclude the PPVA Black Elk (Equity) LLC investment. Figures shown herein are unaudited and may not add due to rounding.

This presentation contains non-GAAP financial information. NMFC's management uses this information in its internal analysis of results and believes that this information may be informative to investors in gauging the quality of NMFC's financial performance, identifying trends in our results and providing meaningful period-to-period comparisons. However, these non-GAAP measures should not be considered in isolation or as a substitute for or superior to any measures of financial performance calculated and presented in accordance with GAAP. Other companies may calculate this or similarly titled non-GAAP measures differently than we do.

The term Adjusted Net Investment Income as used throughout this presentation is not defined under GAAP and is not a measure of operating income, operating performance or liquidity presented in accordance with GAAP. In evaluating its business, NMFC considers and uses Adjusted Net Investment Income as a measure of its operating performance. Adjusted Net Investment Income is defined as net investment income adjusted to reflect income as if the cost basis of investments held at NMFC's IPO date had stepped-up to fair market value as of the IPO date. Under GAAP, NMFC's IPO did not step-up the cost basis of the predecessor operating company's existing investments to fair market value. Since the total value of the predecessor operating company's investments at the time of the IPO was greater than the investments' cost basis, a larger amount of amortization of purchase or issue discount, and different amounts in realized gains and unrealized appreciation, may be recognized under GAAP in each period than if a step-up had occurred. For purposes of the incentive fee calculation, NMFC adjusts income as if each investment was purchased at the date of the IPO (or stepped-up to fair market value). To view the reconciliation of Adjusted Net Investment Income, please see Appendix C at the end of this presentation.

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Important Notices and Safe Harbor Statement (cont.)

The S&P 500 Stock Index (the "S&P 500") is an unmanaged index of 500 widely held, large‐capitalization stocks from a broad variety of industries that is recognized by investors to be generally representative of the performance of the broad domestic economy. The S&P 500 Total Return Index reflects the reinvestment of all dividends and distributions. Please note an investor cannot invest directly in an index. References to the S&P 500 Total Return Index are for illustrative purposes only. The S&P 500 Financial Index comprises those companies included in the S&P 500 that are classified as members of the GICS financial sectors. The S&P 500 Total Return Index and the S&P Financials Index may not be the most appropriate comparison because the indices are unmanaged and significantly more diversified than NMFC. NMFC's investments and portfolio holdings are materially different from the companies represented in the indices. Additionally, due to the allocation differences between the indices and NMFC, NMFC may experience more investment volatility than the unmanaged S&P 500 Index and the S&P 500 Financial Index, which may have accounted for the results of the comparison.

Relevant credit benchmarks include the Credit Suisse Leveraged Loan Index, the Credit Suisse HY Index II and the BDC Index (together, the "Benchmarks"). The Credit Suisse Leveraged Loan Index is an unmanaged market value weighted index designed to represent the universe of U.S. dollar-denominated leveraged loan markets. The Credit Suisse HY Index II is an unmanaged index designed to mirror the investable universe of U.S. dollar-denominated high yield debt market. The loans and other investments held by NMFC may be materially different in composition and diversification as compared to the loans comprising each of the Benchmarks described above. The BDC Index is not a tracked index and includes the median of other business development companies that have been public for as long as NMFC, equal-weighted. The portfolio of loans and other investments held by the BDC Index and relevant Peer Group referenced herein may be materially different in composition and risk profile than that of NMFC. The volatility of an index may be materially different from the performance attained by NMFC. In addition, NMFC's holdings may differ significantly from the securities that comprise the indices. You cannot invest directly in an index.

Throughout the document, Senior Advisors are included in all references to staff members, team members, investment professionals or operating partners/executives unless stated otherwise. Generally, New Mountain Senior Advisors are similar to "Operating Partners" who provide general or specific industry expertise on particular projects or transactions. All

persons listed in the Senior Advisors (Full Access) category are designated "access persons" pursuant to Rule 204A-1 under the Investment Advisers Act of 1940, as amended, and are subject to New Mountain's Code of Ethics, which therefore allows them to be fully included in New Mountain's investment reviews. Based on a variety of factors, Senior Advisers for Special Projects are designated as "non-access persons" and are not subject to New Mountain's Code of Ethics.

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Management Participants

Steven B. Klinsky

Chairman of the Board of Directors

Robert A. Hamwee

Chief Executive Officer and Director

John R. Kline

President, Chief Operating Officer, and Director

Shiraz Y. Kajee

Chief Financial Officer

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Chairman's Overview

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Q3 2021 Net Investment Income ("NII") of $0.31 per weighted average share, above our guidance of $0.30

Q3 2021 regular dividend of $0.30 per share paid on September 30, 2021

• Q4 2021 regular dividend of $0.30 per share announced, based on estimated NII of at least $0.30 per share, payable on December 30, 2021 to holders of record as of December 16, 2021
• September 30, 2021 net asset value ("NAV") of $13.26 per share vs. $13.33 per share on June 30, 2021
• We believe our portfolio continues to be well positioned as a result of our defensive growth investment strategy, which focuses on acyclical, recurring, and predictable business models with long term viability, even in a recessionary environment
• • Just 9 basis points of annual default loss since 2011
  • Two new borrowers were placed on partial non-accrual for Q3 2021, representing $18 million of fair value of our $3 billion portfolio
  • Since our August 5, 2021 earnings call, portfolio company Risk Ratings(1) have generally remained unchanged
• Recovery of stock price from low of $5.02 per share in April 2020 to $14.06 per share on October 29, 2021(2)

1	Risk Ratingassigned based on two metrics: COVID Exposure and Overall Company Strength. Please refer to page 9 for details	5
2	Based on closing share price