Exhibit 99.28 (h)(xxxix)

Mr. David W. Rossmiller

Old Westbury Funds, Inc.

103 Bellevue Parkway

Wilmington, DE 19809

October 15, 2025

Re:         Waiver of Certain Investment Advisory Fees

Dear Mr. Rossmiller:

As you are aware, Bessemer Investment Management LLC (“BIM”) serves as the investment adviser to the Old Westbury All Cap Core Fund, Old Westbury Fixed Income Fund, Old Westbury Credit Income Fund, Old Westbury Municipal Bond Fund, Old Westbury California Municipal Bond Fund, Old Westbury New York Municipal Bond Fund, Old Westbury Short-Term Bond Fund, Old Westbury Total Equity Fund, Old Westbury Small & Mid Cap Strategies Fund and Old Westbury Large Cap Strategies Fund (the “Funds”), each a series of Old Westbury Funds, Inc., pursuant to an investment advisory agreement (the “Agreement”). Under the Agreement, the Funds have each agreed to pay BIM the following fees for providing investment advisory services to the Funds (the “Investment Advisory Fees”):

BIM hereby commits to waive a portion of the Investment Advisory Fees it is entitled to receive from each Fund to the extent necessary to maintain the net operating expense ratio, excluding Fund transaction costs, investment interest expense, dividend expenses associated with securities sold short, acquired fund fees and expenses and after the application of any other waivers of expenses of the All Cap Core Fund at 0.95%, Fixed Income Fund at 0.57%, Credit Income Fund at 0.85%, Municipal Bond Fund at 0.57%, California Municipal Bond Fund at 0.57%, New York Municipal Bond Fund at 0.57%, Short-Term Bond Fund at 0.37%, Total Equity Fund at 0.98%, Small & Mid

Exhibit 99.28 (h)(xxxix)

Cap Strategies Fund at 1.10% and Large Cap Strategies Fund at 1.10% (each an “Investment Advisory Fee Waiver”).

This agreement will remain in effect until October 31, 2028.

This agreement supersedes and replaces all prior agreements and understandings, oral or written, between BIM and the Funds.

This letter may be executed by any physical or electronic means permissible under applicable law and in counterpart, each of which shall be an original but all of which, taken together, shall constitute one and the same document.