Publication of a Supplementary Prospectus

26 June 2026

Publication of Supplementary Prospectus

The following Supplementary Prospectus has been approved by the Financial Conduct Authority and is available for viewing:

The supplementary prospectus dated 26 June 2026 (the “ Supplementary Prospectus ”) supplements the prospectus dated 9 October 2025 (the “ Prospectus ”) relating to the £10,000,000,000 Guaranteed Secured Medium Term Note Programme, with Anglian Water (Osprey) Financing Plc as the issuer and Osprey Acquisitions Limited and Osprey Investco Limited as obligors.

The Supplementary Prospectus should be read and construed in conjunction with the Prospectus.

To view the Supplementary Prospectus, please follow the link below:

  AWOF - Supplementary Prospectus_June 2026.pdf

A copy of the Supplementary Prospectus has been submitted to the National Storage Mechanism and will shortly be available for inspection at: https://data.fca.org.uk/#/nsm/nationalstoragemechanism .

For further information, please contact:

[e-mail]

DISCLAIMER – INTENDED ADDRESSEES

Please note that the information contained in the Prospectus may be addressed to and/or targeted at persons who are residents of particular countries (specified in the Prospectus) only and is not intended for use and should not be relied upon by any person outside these countries and/or to whom the offer contained in the Prospectus is not addressed. Prior to relying on the information contained in the Prospectus you must ascertain from the Prospectus whether or not you are part of the intended addressees of the information contained therein.

In particular, the Prospectus does not constitute an offer of securities for sale in the United States. This is not for   distribution   in the United States. The securities described herein have not been, and will not be, registered under the U.S. Securities Act of 1933, as amended (the "Securities Act"), or under any relevant securities laws of any state of the United States of America and are subject to U.S. tax law requirements. Subject to certain exceptions, the securities may not be offered or sold within the United States or to, or for the account or benefit of, U.S. persons or to persons within the United States of America, as such terms are defined in Regulation S under the Securities Act. There will be no public offering of the securities in the United States.

Your right to access this service is conditional upon complying with the above requirement.

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AWOF - Supplementary Prospectus June 2026

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