UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of June, 2021

Commission File Number 001-36487

Atlantica Sustainable Infrastructure plc

(Exact name of Registrant as Specified in its Charter)

Not Applicable

(Translation of Registrant’s name into English)

Great West House, GW1, 17th floor

Great West Road

Brentford, TW8 9DF

United Kingdom

Tel.: +44 203 499 0465

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

☒ Form 20-F

☐ Form 40-F

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

This Report on Form 6-K is incorporated by reference into the Registration Statement on Form F-3 of the Registrant filed with the Securities and Exchange Commission on August 6, 2018 (File 333-226611).

June 17, 2021 – On June 16, 2021 Atlantica Sustainable Infrastructure plc closed the previously announced acquisition of the 49% equity interest in a 596 MW wind portfolio in the US.

Chief Financial Officer

Francisco Martinez-Davis

E ir@atlantica.com

Investor Relations & Communication

Leire Perez

E ir@atlantica.com

T +44 20 3499 0465

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	ATLANTICA SUSTAINABLE INFRASTRUCTURE PLC

	/s/ Santiago Seage
	Name: Santiago Seage
	Title: Chief Executive Officer

Date: June 17, 2021