X0202 SCHEDULE 13D/A 0001193125-26-260317 0001502287 XXXXXXXX LIVE 1 Class D and Class U Common Shares of Beneficial Interest 06/16/2026 false 0001957892 85914R304 85913Y102 StepStone Private Infrastructure Fund

128 S. TRYON ST. SUITE 1600 CHARLOTTE NC 28202

Jennifer Y. Ishiguro 858-558-9700 StepStone Group LP 4225 Executive Square, Suite 1600 La Jolla CA 90237 0001502287 N StepStone Group LP WC N DE 0.00 0.00 0.00 0.00 0.00 N 0.00 PN Cover pages are limited to one class of security. The cover page of this Schedule 13D filing relates to the Class D Shares outstanding as of the date of this filing. This Schedule 13D/A relates to the following classes of securities of StepStone Private Infrastructure Fund, a Delaware statutory trust registered under the Investment Company Act of 1940 (the "Issuer"): Class D Common Shares of Beneficial Interest (the "Class D Shares") with CUSIP 85914R304 and Class U Common Shares of Beneficial Interest (the "Class U Shares") with CUSIP 85913Y102. As of the date hereof, the Reporting Person directly holds 2,014.252 Class U Shares, representing 1.83% of the Class U Shares outstanding. As of the date hereof, the Reporting Person no longer beneficially owns any Class D Shares and is no longer the beneficial owner of more than 5% of the Class U Shares. This filing represents an exit filing for the Reporting Person with respect to the Class D Shares and Class U Shares. This comment shall serve as full disclosure of the beneficial ownership of the securities of the Issuer. See Item 5. Class D and Class U Common Shares of Beneficial Interest StepStone Private Infrastructure Fund 128 S. TRYON ST. SUITE 1600 CHARLOTTE NC 28202 This Amendment No. 1 ("Amendment No. 1") amends the Statement on Schedule 13D filed by the Reporting Person on June 5, 2026 (as so amended, the "Schedule 13D") and relates to shares of beneficial interest of StepStone Private Infrastructure Fund, a Delaware statutory trust registered under the Investment Company Act of 1940, as amended (the "Issuer"), designated as the Class D Common Shares of Beneficial Interest (the "Class D Shares") and Class U Common Shares of Beneficial Interest (the "Class U Shares" and collectively, the "Common Shares") of the Issuer. Capitalized terms used herein and not otherwise defined herein shall have the meanings assigned to such terms in the Schedule 13D. Items 5(a)-(c) are hereby amended and restated as follows. As of the date hereof, the Reporting Person directly holds 2,014.252 Class U Shares, representing 1.83% of the Class U Shares outstanding. As of the date hereof, the Reporting Person no longer beneficially owns any Class D Shares and is no longer the beneficial owner of more than 5% of the Class U Shares. This filing represents an exit filing for the Reporting Person with respect to the Class D Shares and Class U Shares. See 5(a) above. Except as set forth in this Schedule 13D, the Reporting Person has not effected any transaction in the Common Shares since the filing of the initial Schedule 13D on June 5, 2026. Item 5(c) is hereby amended and restated as follows: On June 16, 2026, 1,007.20 Class D Shares were redeemed by the Issuer at a price of $15.57 per share. Item 5(e) is hereby amended and restated as follows: As of June 8, 2026, the Reporting Person has ceased to be the beneficial ownership of more than five percent of the Issuer's Class U Shares. As of June 16, 2026, the Reporting Person has ceased to be the beneficial owner of more than five percent of the Issuer's Class D Shares. This filing on Schedule 13D constitutes an exit filing for the Reporting Person with respect to the Class U Shares and Class D Shares. StepStone Group LP /s/ Jennifer Y. Ishiguro 06/18/2026