Letter Agreement, dated as of January 25, 2019, among Goldman Sachs Private Middle Market Credit SPV LLC, as borrower, Goldman Sachs Private Middle Market Credit LLC, State Street Bank and Trust Company, as collateral agent, collateral administrator, and securities intermediary and JPMorgan Chase Bank, National Association, as administrative agent and lender

Exhibit 10.1

January 25, 2019

Goldman Sachs Private Middle Market SPV LLC

c/o Goldman Sachs Private Middle Market Credit LLC

200 West Street

New York, NY 10282

Ladies and Gentlemen:

Reference is made to the Loan Agreement dated as of November 21, 2017 (as amended by that certain Amendment No.1 to the Loan Agreement dated as of August 17, 2018 and as further amended, modified and supplemented and in effect from time to time, the “Loan Agreement”), among Goldman Sachs Private Middle Market SPV LLC (“you” or the “Borrower”), Goldman Sachs Private Middle Market Credit LLC, the Financing Providers party thereto, State Street Bank and Trust Company, as collateral agent, collateral administrator and securities intermediary and JPMorgan Chase Bank, National Association, as administrative agent (“JPMorgan” or the “Administrative Agent”). Capitalized terms used and not defined herein shall have the respective meanings assigned to them in the Loan Agreement.

The Borrower and JPMorgan acknowledge that the Borrower submitted an Accordion Option Request on January 17, 2019 to increase the Financing Commitments by an amount equal to $50,000,000. JPMorgan agrees that this Accordion Option Request has been approved in the amount equal to $50,000,000.

Except as expressly set forth in this letter, the Loan Agreement and the other Loan Documents remain unchanged and in full force and effect.

This letter shall be governed by, and construed in accordance with, the law of the State of New York. This letter may be executed in any number of counterparts, each of which shall be an original, and all of which, when taken together, shall constitute one agreement. Delivery of an executed signature page of this letter by electronic transmission shall be effective as delivery of a manually executed counterpart hereof.

[signature pages follow]

Please confirm that the foregoing is our mutual understanding by signing and returning an executed counterpart of this letter.

[Signature Page to Letter Agreement]

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