SW (FINANCE) I PLC

Released

SW (Finance) I PLC

22 June 2026

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

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

Further Equity Commitment

On 1 July 2025, Southern Water announced it was seeking to raise up to £1.2 billion of equity to support its 2025-30 AMP8 investment programme, which is the largest in the sector relative to its existing regulatory asset base, and 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.

On 31 March 2026, Southern Water announced that it had already received £900 million of this equity support from Sandstone Bidco Limited ("SBL"), via funds managed by Macquarie Asset Management ("MAM"), in two tranches in November 2025 and March 2026 respectively pursuant to equity commitments provided by SBL to Southern Water in July and December 2025.

Southern Water also announced that SBL had reconfirmed its intention (previously announced on 30 December 2025) to provide up to a further £300 million of binding equity commitments by 30 June 2026 (the "Third AMP8 Equity Commitment").

Southern Water is pleased to announce that it has secured a binding Third AMP8 Equity Commitment from SBL of £300 million, being the top of the range that SBL had previously indicated. Also as previously indicated, Southern Water expects to draw down in full the Third AMP8 Equity Commitment on or around 31 March 2027.

The majority of the Third AMP8 Equity Commitment is being funded by subscriptions for new shares in the Southern Water group by Asterion Industrial Partners ("Asterion"), an independent European infrastructure investment manager headquartered in Madrid, with the balance of the Third Equity Commitment being funded by further subscription for shares in the Southern Water group by funds managed by MAM. Following completion, Asterion will become a new minority shareholder in the Southern Water group, with MAM-managed funds remaining the majority shareholder. The Third AMP8 Equity Commitment is unconditional in all respects save for the receipt of clearance under Council Regulation (EC) No 139/2004 ("EUMR") in respect of Asterion's investment, for which a filing is being made to the European Commission today.

With this Third AMP8 Equity Commitment, in aggregate, shareholders' total equity commitments to the Southern Water group since 2021 now exceed £2.8 billion. No distributions have been paid to external shareholders since 2017.

In the first year of the AMP8 period (the year ended 31 March 2026), Southern Water delivered further improvements across a number of operational metrics - including reducing water supply interruptions, water leakage, and external sewer flooding - alongside a record level of capital investment in its network. Southern Water remains focused on addressing the underlying drivers of pollution incidents, alongside ongoing improvements in operational response, asset performance and targeted investment in higher-risk areas, building on the investment in asset health and operations since 2021 and supporting its commitment to further reductions in the years ahead.

Lawrence Gosden, Chief Executive Officer of Southern Water, said:

"Over the past four years, we have worked hard to transform Southern Water, improving operational performance while significantly increasing investment in the services and infrastructure our customers rely on every day. We are seeing the benefits of that progress, but we remain focused on the substantial work still ahead.

"This additional equity support enables us to enhance our financial resilience and build on that momentum as we deliver our ambitious £8.5 billion investment programme over the next five years. It will help us improve services for customers, strengthen the resilience of our infrastructure and continue reducing our environmental impact.

"We are grateful for the continued support of Macquarie, whose long-term investment and industrial support have been instrumental in supporting our turnaround. We are also pleased to welcome Asterion Industrial Partners as a new shareholder. Their investment represents a strong endorsement of the progress we have made and confidence in our plans for the future. We look forward to working with them as we continue delivering for customers, communities and the environment."

As announced on 31 March 2026, SBL also intends to support Southern Water to further reduce its leverage (as measured by the ratio of net debt to regulatory capital value) from circa 67 per cent as at 31 March 2026 (down from 74% at 31 March 2025 to 65 per cent by 2029, even as it funds its large investment programme.

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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