Post-Effective Amendment to Post-Effective Amendment by Investment Company (Form 485BXT)

As filed with the U.S. Securities and Exchange Commission on July 18, 2025

File No. 333-271700

File No. 811-23872

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	☒
Pre-Effective Amendment No.	☐
Post-Effective Amendment No. 43	☒
and/or
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	☒
Amendment No. 45	☒

Themes ETF Trust

(Exact Name of Registrant as Specified in Charter)

34 East Putnam Avenue, Suite 112

Greenwich, CT 06830

(Address of Principal Executive Offices, Zip Code)

(646) 206-1788

(Registrant's Telephone Number, including Area Code)

Jose C. Gonzalez

34 East Putnam Avenue, Suite 112

Greenwich, CT 06830

(Name and Address of Agent for Service)

Copy to:

Karen Aspinall, Esq.

Practus, LLP

11300 Tomahawk Creek Parkway, Suite 310

Leawood, Kansas 66211

[email protected]

It is proposed that this filing will become effective

☐	immediately upon filing pursuant to paragraph (b)
☒	On August 1, 2025, pursuant to paragraph (b)
☐	60 days after filing pursuant to paragraph (a)(1)
☐	on pursuant to paragraph (a)(1)
☐	75 days after filing pursuant to paragraph (a)(2)
☐	on ________________ pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box

☒	this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

EXPLANATORY NOTE

The sole purpose of this filing is to delay the effectiveness of Post-Effective Amendment No. 31 (the "Amendment") to the Registrant's Registration Statement (filed on May 7, 2025) with respect to 15 of its series (Leverage Shares 2X Long HIMS Daily ETF, Leverage Shares 2X Long BBAI Daily ETF, Leverage Shares 2X Long SOUN Daily ETF, Leverage Shares 2X Long RGTI Daily ETF, Leverage Shares 2X Long COST Daily ETF, Leverage Shares 2X Long VST Daily ETF, Leverage Shares 2X Long RKLB Daily ETF, Leverage Shares 2X Long AFRM Daily ETF, Leverage Shares 2X Long GOLD Daily ETF, Leverage Shares 2X Long NEM Daily ETF, Leverage Shares 2X Long OKLO Daily ETF, Leverage Shares 2X Long FUTU Daily ETF, Leverage Shares 2X Long PDD Daily ETF, Leverage Shares 2X Long JD Daily ETF, Leverage Shares 2X Long ABNB Daily ETF) until August 1, 2025. Parts A and B of the Amendment are incorporated by reference herein. This amendment also incorporates by reference the information contained in Part C of Post-Effective Amendment No. 42 to the Registrant's Registration Statement, which was filed on July 17, 2025.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 (the "Securities Act") and the Investment Company Act of 1940, the Trust certifies that it meets all of the requirements for effectiveness of this Post-Effective Amendment to its Registration Statement on Form N-1A under Rule 485(b) under the Securities Act and has duly caused this Post-Effective Amendment No. 43 to the Registrant's Registration Statement to be signed on its behalf by the undersigned, duly authorized, in the City of Greenwich, State of Connecticut, on this 18^th day of July, 2025.

THEMES ETF TRUST
By:	/s/ Jose C. Gonzalez
Jose C. Gonzalez
Trustee and President (Principal Executive Officer)

Pursuant to the requirements of the Securities Act, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

Signature		Title		Date
/s/ Jose C. Gonzalez		Trustee and President		July 18, 2025
Jose C. Gonzalez		(Principal Executive Officer)
/s/ Dobromir Kamburov		Treasurer		July 18, 2025
Dobromir Kamburov*		(Principal Financial Officer and Principal Accounting Officer)
/s/ Sanjay R. Bharwani		Trustee		July 18, 2025
Sanjay R. Bharwani*
/s/ Neil Fleming		Trustee		July 18, 2025
Neil Fleming*
/s/ Tracy N. Packwood		Trustee		July 18, 2025
Tracy N. Packwood*

*By:	/s/ Jose C. Gonzalez
	Jose C. Gonzalez
	July 18, 2025

Attorney-in-Fact pursuant to Powers of Attorney previously filed with Pre-Effective Amendment No. 2 to the Registrant's registration statement on November 9, 2024