Atlantica Announces Tender Offer for up to $85 Million of Green Senior Secured Notes due 2028

November 3, 2025 - Atlantica Sustainable Infrastructure Ltd (“Atlantica” or the “Company”) today announced a cash tender offer (the “Tender Offer”) to purchase for cash up to $85 million aggregate principal amount of its 4.125% Green Senior Secured Notes due 2028 (the “2028 Notes”). The Tender Offer is made only by and pursuant to the terms of the Offer to Purchase, dated November 3, 2025 (as amended or supplemented from time to time, the “Offer to Purchase”). Certain information regarding the 2028 Notes and the terms of the Tender Offer is summarized in the table below.

CUSIP No. / ISIN	OutstandingPrincipal Amount	Tender Cap	Title of Security	Tender Offer Consideration(1)(2)		Early Tender Payment(1)	Total Consideration(1)(2)(3)
CUSIP No. 04916WAA2 (144A) G0751NAB9 (REG S)	$400,000,000	$85,000,000	4.125% Green Senior Secured Notes due 2028	$940.00	$50.00		$990.00
ISIN US04916WAA27 (144A) USG0751NAB94 (REG S)

(1)    Per $1,000 principal amount of Notes accepted for purchase.

(2)    Excludes Accrued Interest, which will be paid in addition to the Tender Offer Consideration or the Total Consideration, as applicable.

(3)    Includes the applicable Early Tender Payment.

The Tender Offer is subject to, and conditioned upon, the satisfaction or waiver of certain conditions described in the Offer to Purchase, including the consummation of the concurrently announced offering of green senior notes on terms satisfactory to Atlantica and Atlantica Sustainable Infrastructure Group plc in their sole discretion and certain other general conditions, in each case as described more fully in the Offer to Purchase. The Tender Offer is open to all registered holders of the 2028 Notes.

Key Dates & Other Information

• The Tender Offer will expire at 5:00 p.m. Eastern Time on December 3, 2025 (such time and date, as the same may be extended, the “Expiration Date”). Tendered 2028 Notes may be withdrawn at any time prior to 5:00 p.m. Eastern Time on November 17, 2025 (subject to certain extensions as may be required by law). Holders of 2028 Notes must validly tender and not validly withdraw their 2028 Notes before the Expiration Date to be eligible to receive any consideration for their 2028 Notes.
• 2028 Notes validly tendered and not validly withdrawn at or prior to 5:00 p.m. Eastern Time, on November 17, 2025 (“Early Tender Deadline”) will be eligible to receive the Total Consideration, which includes the early tender payment set forth in the table above (the “Early Tender Payment”). 2028 Notes validly tendered after the Early Tender Date and not validly withdrawn at or prior to the Expiration Date will be eligible to receive the Tender Offer Consideration, which is equal to the Total Consideration minus the Early Tender Payment.
• The total consideration (“Total Consideration”) for each $1,000 in principal amount of 2028 Notes is set forth in the table above.
• In addition, accrued and unpaid interest to, but excluding, the applicable Settlement Date (as defined below) will be paid in cash on all validly tendered 2028 Notes accepted for purchase in the Tender Offer.
• The settlement date for the 2028 Notes validly tendered and not validly withdrawn at or prior to the Early Tender Date and accepted for purchase is expected to be November 19, 2025, the second business day after the Early Tender Date (the “Initial Settlement Date”). The settlement date for the 2028 Notes validly tendered after the Early Tender Date but at or prior to the Expiration Date and accepted for purchase is expected to be December 5, 2025, the second business day after the Expiration Date (the “Final Settlement Date”).
• The Tender Offer is being made by Atlantica Sustainable Infrastructure Ltd.

Parties & Contacts:

Barclays Capital Inc. is acting as dealer manager for the Tender Offer (the “Dealer Manager”). For questions regarding the Tender Offer, the Dealer Manager can be contacted at (collect) (212) 528-7581, (toll-free) (800) 438-3242 or by email to us.lm@barclays.com.

Copies of the Offer to Purchase are available to holders of 2028 Notes from Global Bondholder Services Corporation, the information agent and the tender agent for the Tender Offer. Requests for copies of the Offer to Purchase and any questions regarding the Tender Offer should be directed to Global Bondholder Services Corporation, at their addresses set forth below:

Global Bondholder Services Corporation

65 Broadway – Suite 404

New York, New York 10006

Call Toll-Free: (855)-654-2015

Banks and Brokers Only: (212) 430-3774

Email: contact@gbsc-usa.com

The information contained herein is not for publication or distribution, directly or indirectly, in any jurisdiction where the distribution of such information is restricted by law, and does not constitute an offer to sell, or a solicitation of an offer to buy securities.

The Offer to Purchase has not been filed with the U.S. Securities and Exchange Commission (the “SEC”), 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. 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 a solicitation of an offer to sell the 2028 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 2028 Notes from, holders in any jurisdiction in which the Tender Offer or the acceptance thereof would not be in compliance with the securities of blue sky laws of such jurisdiction. No recommendation is made as to whether holders should tender their 2028 Notes. Holders of 2028 Notes should carefully read the Offer to Purchase because it contains important information, including the various terms and conditions of the Tender Offer

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 consummation of the Tender Offer and the offering of the green senior notes. 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).

Chief Financial Officer Leire Perez E ir@atlantica.com

Communication Irene Rodriguez E ir@atlantica.com T +44 20 3807 6709