Centrica plc

4^th November 2025

Completion of investment in Sizewell C

Centrica plc (the "Company") is pleased to announce the completion of its acquisition of a 15% equity stake in Sizewell C¹ following financial close and revenue commencement which occurred earlier today. As part of completion, Centrica plc has made an initial investment of £376 million into Sizewell C, which includes funding of the regulated asset base value built up prior to financial close and pre-funding a portion of 2026 construction costs. We now expect to make a cumulative investment of £500 - 600 million into Sizewell C through to the end of 2028 as part of our capped £1.3 billion investment.

Chris O'Shea, Group Chief Executive, Centrica plc, said:

"Today is a significant milestone for the UK, and I'm thrilled that Centrica is joining forces with exceptional partners to drive this critical project forward. Sizewell C will be at the heart of Britain's energy future - delivering reliable, affordable, zero-carbon power that fuels economic growth for decades to come. This investment goes far beyond building a new power station; it's a huge commitment to Britain's energy security, our journey to net zero, and the creation of thousands of high-quality jobs nationwide.

"Centrica's investment in the backbone of the UK's energy system, from Sizewell C, to Grain LNG, to our partnership with X-energy, is securing the energy Britain needs today and powering the ambitions of tomorrow. We stand ready to continue to invest if we see a supportive regulatory framework."

Enquiries:

Slaughter and May is acting as legal adviser to Centrica.

Notes:

1.   Further details can be found at www.centrica.com/sizewellc

Disclaimer

UBS AG London Branch ("UBS") is authorised and regulated by the Financial Market Supervisory Authority in Switzerland. It is authorised by the Prudential Regulation Authority and subject to regulation by the Financial Conduct Authority and limited regulation by the Prudential Regulation Authority in the United Kingdom. UBS are acting as financial adviser exclusively for Centrica and no one else in connection with the matters set out in this announcement. In connection with such matters, UBS, its affiliates, and it's or their respective directors, officers, employees and agents will not regard any other person as its client, nor will it be responsible to any other person for providing the protections afforded to its clients or for providing advice in relation to the contents of this announcement or any other matter referred to herein.

END

Centrica plc is listed on the London Stock Exchange (CNA)

Registered Office: Millstream, Maidenhead Road, Windsor, Berkshire SL4 5GD

Registered in England & Wales number: 3033654

Legal Entity Identifier number: E26EDV109X6EEPBKVH76

ISIN number: GB00B033F229