June 26, 2026

VIA EDGAR TRANSMISSION

U.S. Securities and Exchange Commission

Division of Investment Management

100 F Street, NE

Washington, DC 20549

Re:

Themes ETF Trust (the “Trust”)

File Nos.: 333-271700 and 811-23872

Leverage Shares 2X Long META Daily ETF

Leverage Shares 2X Long AAPL Daily ETF

Leverage Shares 2X Long AMZN Daily ETF

(collectively, the “Funds”)

Ladies and Gentlemen:

Pursuant to Rule 497(j) under the Securities Act of 1933, as amended, and the regulations thereunder, the Trust, on behalf of the Funds, hereby certifies that the form of Prospectus and Statement of Additional Information that would have been filed under Rule 497(b) or (c) would not have differed from those contained in Post-Effective Amendment No. 266 to the Trust’s Registration Statement on Form N-1A, filed on June 26, 2026.

If you have any questions or require further information, please contact Karen Aspinall at (949) 629-3928 or Karen.Aspinall@Practus.com.

Sincerely,

/s/ Karen Aspinall

Karen Aspinall

KAREN A. ASPINALL ● PARTNER

11300 Tomahawk Creek Pkwy ● Ste. 310 ● Leawood, KS 66211 ● p: 949.629.3928

Practus, LLP ● Karen.Aspinall@Practus.com ● Practus.com