Richard J. Coyle Partner

Chapman and Cutler LLP 320 South Canal Street Chicago, Illinois 60606   T 312.845.3724 rcoyle@chapman.com

October 7, 2025

U.S. Securities and Exchange Commission

Division of Investment Management

100 F Street, N.E.

Washington, D.C. 20549

Ladies and Gentlemen:

On behalf of Roundhill ETF Trust (the “Registrant”), in accordance with the provisions of Rule 497(j) of Regulation C under the Securities Act of 1933 (the “Securities Act”), this letter serves to certify that the recent amendment to the Registration Statement on Form N-1A (the “Registration Statement”) for the Registrant for Roundhill Meme Stock ETF, a series of the Registrant, does not differ from that which would have been filed pursuant to Rule 497(c) of the Securities Act.  Post-Effective Amendment No. 186 was filed electronically with the Securities and Exchange Commission on October 6, 2025.

If we may cooperate with you in any way in the processing of this registration statement, please telephone the undersigned at (312) 845-3724.

Enclosures