RNS Number : 7490J Pennon Group PLC 01 December 2025

Pennon Group plc - LEI: 213800V1CCTS41GWH423

South West Water Finance Plc - LEI: 213800OV68U446W4NV89

South West Water Limited - LEI: 213800FR2VAOKRYRHX45

EMTN Programme: Publication of Supplementary Prospectus

The following Supplementary Prospectus is available for viewing:

Supplementary prospectus dated 1 December 2025 (the "Supplementary Prospectus") supplementing the Base Prospectus dated 21 August 2025 as supplemented, amended or updated from time to time (the "Base Prospectus") relating to the GBP 2,500,000,000 Euro Medium Term Note Programme established by South West Water Finance PLC and unconditionally and irrevocably guaranteed by South West Water Limited.

To view the Supplementary Prospectus, please paste the following URL into the address bar of your browser:

First Supplementary Prospectus Dated 1 December 2025 To The Base Prospectus Dated 21 August 2025

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 Chris Tregenna, Group Treasurer, on 07733 312479.

DISCLAIMER - INTENDED ADDRESSEES

Please note that the information contained in the Supplementary Prospectus and the Base Prospectus may be addressed to and/or targeted at persons who are residents of particular countries (specified in the Base 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 Base Prospectus as supplemented by the Supplementary Prospectus is not addressed. Prior to relying on the information contained in the Base Prospectus and the Supplementary Prospectus you must ascertain from the Base Prospectus and the Supplementary Prospectus whether or not you are part of the intended addressees of the information contained therein.

In particular, this announcement is not for distribution in the United States and the notes offered by the Base Prospectus 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 notes offered by the Prospectus in the United States.

This announcement does not constitute or form part of an offer to sell or the solicitation of an offer to subscribe for or otherwise acquire any securities.

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

END

RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the London Stock Exchange use the personal data you provide us, please see our Privacy Policy. END PSPUAOVRVBUURAA