Atlantica Sustainable Infrastructure LTD

Atlantica announces early tender results for its green senior secured notes due 2028

November 18, 2025 - Atlantica Sustainable Infrastructure Ltd (“Atlantica” or the “Company”) announced today the early tender results of the previously announced tender offer (the “Tender Offer”) to purchase for cash up to $85 million in aggregate principal amount of its outstanding $400 million aggregate principal amount of its 4.125% Green Senior Secured Notes due 2028 (CUSIP Nos.: 04916WAA2 (144A) / G0751NAB9 (Reg S) / ISIN Nos.: US04916WAA27 (144A) / USG0751NAB94 (Reg S)) (the “Notes”) (such amount, the “Tender Cap”). The Tender Offer is being made pursuant to the terms of an offer to purchase dated November 3, 2025 (as may be amended or supplemented from time to time, the “Offer to Purchase”), and is subject to certain conditions, including the Financing Condition, as described therein.

Details of the Tender Offer

The Company has been advised by Global Bondholder Services Corporation, as information agent and tender agent, that as of 5:00 p.m., New York City time, on November 17, 2025 (“Early Tender Deadline”), $335,501,000 aggregate principal amount of Notes, representing approximately 84% of the outstanding Notes, had been validly tendered and not validly withdrawn. Subject to the terms and conditions of the Tender Offer described in the Offer to Purchase, the Company intends to accept for purchase $85 million aggregate principal amount of the Notes validly tendered (and not validly withdrawn) at or prior to the Early Tender Deadline.

The consideration for each $1,000 principal amount of Notes validly tendered (and not validly withdrawn) at or prior to the Early Tender Deadline and accepted for purchase pursuant to the Tender Offer (the “Early Tender Notes”) will be $990 (the “Total Consideration”). The Total Consideration includes an early tender payment equal to $50 per $1,000 principal amount of Notes. Holders of Notes (“Holders”) whose Notes are accepted for purchase in the Tender Offer will also receive accrued and unpaid interest on such Notes from the last interest payment date to, but not including, the applicable settlement date. The Company expects the settlement date with respect to the Early Tender Notes to be November 19, 2025.

In accordance with the terms of the Tender Offer, the withdrawal time of 5:00 p.m., New York City time, on November 17, 2025, has now passed. Accordingly, Notes validly tendered in the Tender Offer may not be withdrawn, except in limited circumstances where required by law. Although the Tender Offer is scheduled to expire at 5:00 p.m., New York City time, on December 3, 2025, because the Tender Cap has been reached in respect of tenders of Notes made at or prior to the Early Tender Deadline, Atlantica does not expect to accept for purchase any Notes tendered after the Early Tender Deadline.

Parties & Contacts

Barclays Capital Inc. is acting as the dealer manager for the Tender Offer and can be contacted with questions regarding the Tender Offer at the following telephone numbers and email addresses:

Barclays Capital Inc.

745 Seventh Avenue, 5th Floor

New York, New York 100019

Attention: Liability Management Group

Collect: +1 (212) 528-7581

Toll Free: +1 (800) 438-3242

Email: us.lm@barclays.com

Copies of the Offer to Purchase are available to Holders from Global Bondholder Services Corporation, the information agent and the tender agent for the Tender Offer. Requests for copies of the Offer to Purchase should be directed to:

Global Bondholder Services Corporation

By Mail, Overnight Courier or Hand Delivery:

65 Broadway, Suite 404

New York, NY 10006

Attn: Corporate Action

Email: contact@gbsc-usa.com

Banks and Brokers Call Collect: +1 (212) 430-3774

All Others, Call Toll Free: +1 (855) 654-2015

Important Notice

The Tender Offer is being made solely on the terms and conditions set forth in the Offer to Purchase. Under no circumstances shall this press release constitute an offer to buy or the solicitation of an offer to sell the Notes or any other securities of the Company or any of its affiliates. The Tender Offer is not being made to, nor will the Company accept tenders of Notes from, Holders in any jurisdiction in which the Tender Offer would not be in compliance with the securities laws of such jurisdiction. No recommendation is made by BNY Mellon Corporate Trustee Services Limited, as trustee, the Company, the dealer manager or the information agent and the tender agent as to whether Holders should tender their Notes with respect to the Tender Offer. If any holder of Notes is in any doubt as to the action it should take, it is recommended to seek its own legal, tax, accounting and financial advice, including as to any tax consequences, immediately from its stockbroker, bank manager, attorney, accountant or other independent financial or legal adviser. Any individual or company whose Notes are held on its behalf by a broker, dealer, bank, custodian, trust company or other nominee or intermediary must contact such entity if it wishes to participate in the Tender Offer. Holders should carefully read the Offer to Purchase because it contains important information, including the various terms and conditions of the Tender Offer.

Neither the Offer to Purchase nor any related documents have been filed with the U.S. Securities and Exchange Commission, nor have any such documents been filed with or reviewed by any federal or state securities commission or regulatory authority of any country. No authority has passed upon the accuracy or adequacy of the Offer to Purchase or any related documents, and it is unlawful and may be a criminal offense to make any representation to the contrary.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of United States securities laws. Any statements that express, or involve discussions as to, expectations, beliefs, plans, objectives, assumptions, strategies, future events or performance (often, but not always, through the use of words or phrases such as may result, are expected to, will continue, is anticipated, likely to be, believe, will, could, should, would, estimated, may, plan, potential, future, projection, goals, target, outlook, predict, aim and intend or words of similar meaning) are not statements of historical facts and may be forward looking. Such statements occur throughout this press release and include, but are not limited to, statements relating to the use of proceeds from the offering of the green senior notes due 2032 and the consummation of the Tender Offer. Forward-looking statements involve estimates, assumptions and uncertainties. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including uncertainties related to market conditions and the completion of the offering on the anticipated terms or at all, the other factors discussed in the Offer to Purchase. Any forward-looking statement speaks only as of the date on which such statement is made, and Atlantica undertakes no obligation to update any forward-looking statement to reflect events or circumstances, including, but not limited to, unanticipated events, after the date on which such statement is made, unless otherwise required by law. New factors emerge from time to time, and it is not possible for management to predict all of these factors, nor can it assess the impact of each of these factors on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained or implied in any forward-looking statement.

About Atlantica

Atlantica Sustainable Infrastructure Ltd. is a sustainable infrastructure company that owns a diversified portfolio of contracted renewable energy, storage, efficient natural gas, electric transmission, and water assets in North America, Europe, and South America (www.atlantica.com).