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EX-99.1

2 tslx-ex99_1.htm

EX-99.1

EX-99.1

Exhibit 99.1

k

FIRST QUARTER 2026 EARNINGS RESULTS

Sixth Street Specialty Lending, Inc. Reports First Quarter Results; Declares a Second Quarter Base Dividend Per Share of $0.42

NEW YORK — May 5, 2026 — Sixth Street Specialty Lending, Inc. (NYSE: TSLX, or the “Company”) today reported net investment income of $0.42 per share and net loss of $0.27 per share for the first quarter ended March 31, 2026. These results correspond to an annualized return on equity (ROE) on net investment income and net income of 9.9% and -6.5%, respectively. Reported and adjusted metrics converged this quarter, as there was no impact related to capital gains incentive fees.

Reported net asset value (NAV) per share was $16.24 at March 31, 2026 as compared to NAV per share of $16.98 or an adjusted NAV per share of $16.97 at December 31, 2025 (which accounts for the impact of the $0.01 per share fourth quarter 2025 supplemental dividend). The main driver of this quarter’s NAV per share decline was $0.58 per share attributable to movement in fair value from market inputs. This included $0.40 per share from unrealized losses in the debt portfolio tied to credit spread widening seen in the broader market and $0.18 per share from lower market valuations in the Company’s limited equity portfolio.

The Company announced that its Board of Directors has declared a second quarter 2026 base dividend of $0.42 per share to shareholders of record as of June 15, 2026, payable on June 30, 2026. The decision to revise the base dividend level was informed by what the Company believes is a responsible and sustainable dividend policy. The supplemental dividend policy remains in place to distribute over-earning to shareholders based on the existing framework.

On May 1, 2026, the Company completed an amendment to its Revolving Credit Facility, which extended the stated maturity date to May 1, 2031 for $1.525 billion of commitments. The pricing and other material terms of the facility remain unchanged.

Net Investment Income Per Share

Q1 2026:

$0.42

Net Loss Per Share

Q1 2026:

$0.27

Return on Equity

Q1 2026 (NII):

9.9%

Q1 2026 (NI):

(6.5)%

NAV

Q1 2026 ($MM):

$1,542.7

Q1 2026 (per share):

$16.24

Dividends Declared (per share)

Q1 2026 (Base):

$0.46

LTM Q1 2026 (Base):

$1.84

LTM Q1 2026 (Supplemental):

$0.15

LTM Q1 2026 (Total):

$1.99

1

Portfolio and Investment Activity

For the quarter ended March 31, 2026, new investment commitments totaled $338.1 million. This compares to $242.4 million for the quarter ended December 31, 2025.

For the quarter ended March 31, 2026, the principal amount of new investments funded was $134.8 million across two new portfolio companies, four upsizes to existing portfolio companies and an initial investment in the previously announced joint venture, Structured Credit Partners. For this period, the Company had $113.0 million aggregate principal amount in exits and repayments. For the quarter ended December 31, 2025, the principal amount of new investments funded was

$196.7 million across five new portfolio companies and four upsizes to existing portfolio companies. For this period, the Company had $234.9 million aggregate principal amount in exits and repayments.

The Company had investments in 1431 portfolio companies as of March 31, 2026 and December 31, 2025 with an aggregate fair value of $3,313.4 million and $3,347.3 million, respectively. As of March 31, 2026, the average investment size in each portfolio company was $30.1 million based on fair value.

As of March 31, 2026, the Company’s portfolio based on fair value consisted of 89.3% first-lien debt investments, 1.0% second-lien debt investments, 1.9% mezzanine debt investments, 4.6% equity investments, 2.8% structured credit investments and 0.4% joint venture investments. As of December 31, 2025, the Company’s portfolio based on fair value consisted of 89.2% first-lien debt investments, 0.9% second-lien debt investments, 1.8% mezzanine debt investments, 5.2% equity and other investments and 2.9% structured credit investments.

As of March 31, 2026, 96.3% of debt investments2 based on fair value in the portfolio bore interest at floating rates with 100.0% of these subject to reference rate floors. The Company’s credit facilities also bear interest at floating rates. In connection with the Company’s Unsecured Notes, which bear interest at fixed rates, the Company has entered into fixed-to-floating interest rate swaps in order to align the nature of the interest rates of its liabilities with its investment portfolio.

As of March 31, 2026 and December 31, 2025, the weighted average total yield of debt and income-producing securities at fair value (which includes interest income and amortization of fees and discounts) was 11.1% and 11.1%, respectively, and the weighted average total yield of debt and income-producing securities at amortized cost (which includes interest income and amortization of fee

8-K

false000150865500015086552026-02-122026-02-12

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): February 12, 2026

Sixth Street Specialty Lending, Inc. (Exact name of registrant as specified in charter)

Delaware

001-36364

27-3380000

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(I.R.S. Employer Identification No.)

2100 McKinney Avenue, Suite 1500 Dallas, TX

75201

(Address of Principal Executive Offices)

(zip code)

Registrant’s telephone number, including area code: (469) 621-3001

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock, par value $0.01 per share

TSLX

The New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02 – Results of Operations and Financial Condition On February 12, 2026, Sixth Street Specialty Lending, Inc. (the “Company”) issued a press release announcing its financial results for the year ended December 31, 2025. The text of the press release is included as Exhibit 99.1 to this Form 8-K. The information disclosed under this Item 2.02, including Exhibit 99.1 hereto, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 and shall not be deemed incorporated by reference into any filing made under the Securities Act of 1933, except as expressly set forth by specific reference in such filing. Item 7.01 – Regulation FD Disclosure On February 12, 2026, the Company issued a press release, included herewith as Exhibit 99.1, announcing the declaration of a first quarter 2026 base dividend per share of $0.46 to shareholders of record as of March 16, 2026, payable on March 31, 2026, and a fourth quarter 2025 supplemental dividend per share of $0.01 to shareholders of record as of February 27, 2026, payable on March 20, 2026. The information disclosed under this Item 7.01, including Exhibit 99.1 hereto, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, and shall not be deemed incorporated by reference into any filing made under the Securities Act of 1933, except as expressly set forth by specific reference in such filing. Item 9.01 – Financial Statements and Exhibits (d) Exhibits:

Exhibit Number

Description

99.1

Press Release, dated February 12, 2026

104

The cover page of this Current Report on Form 8-K, formatted in Inline XBRL

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

SIXTH STREET SPECIALTY LENDING, INC.

(Registrant)

Date: February 12, 2026

By:

/s/ Ian Simmonds

Ian Simmonds

Chief Financial Officer