Prospectus Certification by Investment Company (Form 497J)

MainGate Trust

c/o U.S. Bank Global Fund Services

615 E. Michigan Street

Milwaukee, WI 53202

April 3, 2026

VIA EDGAR TRANSMISSION

United States Securities and Exchange Commission

Division of Investment Management

100 F Street, N.E.

Washington, D.C. 20549

Re:

MainGate Trust (the "Trust")

File Nos.: 333-170422 and 811-22492

Dear Sir or Madam:

Pursuant to Rule 497(j) under the Securities Act of 1933 (the "1933 Act"), as amended, and pursuant to the Investment Company Act of 1940, as amended, and the regulations thereunder, the trust on behalf of its series, the MainGate MLP Fund, hereby certifies that the forms of Prospectus and Statement of Additional Information that would have been filed under Rule 497(c) under the 1933 Act would not have differed from that contained in the most recent amendment to the Trust's registration statement dated March 31, 2026, and filed electronically as Post-Effective Amendment No. 26 to the Trust's Registration Statement on Form N-1A on March 27, 2026.

If you have any questions regarding the enclosed, please contact the undersigned at (907) 406-2325 or [email protected].

Sincerely,

/s/ Nicole Washington

Nicole Washington

For U.S. Bank Global Fund Services

as Administrator to the Trust