Equity Commitment Draw Down

SW (FINANCE) I PLC

Released

SW (Finance) I PLC

31 March 2026

SW (FINANCE) I PLC (the "Company")

SOUTHERN WATER SERVICES LIMITED ("Southern Water" and together with the Company, the "SW Group")

Equity Commitment Draw Down

Southern Water is pleased to announce that it has today received £395 million of equity funding from Sandstone Bidco Limited ("SBL") from funds managed by Macquarie Asset Management ("MAM").

This funding draw down comprises the remaining £150 million balance of the £655 million Initial AMP8 Equity Commitment announced on 1 July 2025 (in respect of which, as announced on 13 November 2025, Southern Water received £505 million on 13 November 2025) and the £245 million Second AMP8 Equity Commitment, which was announced on 30 December 2025.

Following receipt of today's funding, Southern Water has now received aggregate equity funding of £900 million since July 2025. In aggregate, shareholders' total investment in the Southern Water group since 2021 now exceeds £2.5 billion.

The proceeds of the equity funding will support Southern Water's AMP8 record investment programme, which is delivering additional capacity and resilience to Southern Water's infrastructure and services to meet new legislation, increased environmental standards and the impacts of climate change, as well as the expectations of its customers.

As announced on 30 December 2025, SBL also intends to:

- provide up to a further £300 million of binding equity commitments (the "Third AMP8 Equity Commitment") by 30 June 2026, with the anticipated draw down of these funds by Southern Water expected on or before 31 March 2027; and

- support Southern Water to further reduce its leverage (as measured by the ratio of net debt to regulatory capital value) from circa 74 per cent as at 31 March 2025 to 65 per cent from 2029 onwards.

With the £900 million of equity funding provided since July 2025, the Company expects its leverage (as measured by the ratio of net debt to regulatory capital value) as at 31 March 2026 to be circa 67 per cent.

Liquidity

Southern Water has continued its pro-active approach to maintaining a strong liquidity position.

As at 31 March 2026, the Company has cash and cash equivalents of circa £1.3 billion. In addition to this, the Company maintains a £350 million revolving credit facility (which is currently undrawn), liquidity facilities of £190 million (which remain fully available) and a £500 million bond backstop facility.

Since the Initial AMP8 Equity Commitment announced on 1 July 2025, the Company has also:

- successfully issued circa £1.9 billion of fixed rate Class A Bonds;

- repaid £350 million of fixed rate Class A Bonds that matured in March 2026; and

- paid down circa £0.5 billion of debt accretion accrued under existing inflation-linked debt instruments, which was due to be paid by June 2026.

For further information, please contact Stuart Ledger (Group CFO) at:

Address: Southern House, Yeoman Road, Worthing, BN13 3NX, United Kingdom

Tel: 01903 272 611

Email: [email protected]

DISCLAIMER - INTENDED ADDRESSEES

This announcement is released by Southern Water Services Limited and contains inside information for the purposes of Article 7 of the Market Abuse Regulation (EU) 596/2014 as it forms part of United Kingdom assimilated domestic law by virtue of the European Union (Withdrawal) Act 2018 ("UK MAR"), encompassing information relating to the matters described above. For the purposes of UK MAR and Article 2 of Commission Implementing Regulation (EU) 2016/1055 as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018, this announcement is made by Richard Manning (Company Secretary) at Southern Water Services Limited.

This announcement is a communication to the market. Nothing in this announcement constitutes an offer of securities for sale in the United States or any other jurisdiction. This announcement does not constitute a prospectus or a prospectus equivalent document.

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