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

(LEGAL ENTITY IDENTIFIER: 549300BHN1HB5BNG2R96)

CORPORATE UPDATE: CREDIT RATING UPGRADE

28 July 2026

Fitch Ratings has announced today that it has upgraded the Company's underlying senior secured debt rating from BBB- to BBB, with a stable outlook.

The upgrade reflects Fitch's recognition of the sustained equity support from funds managed by Macquarie Asset Management and, latterly, Asterion Industrial Partners, as announced by the Company on 22 June 2026, against a backdrop of an ongoing operational turnaround, improved outcome delivery incentives and environmental performance and an uplift in allowances resulting from the Competition and Markets Authority appeal.

The detailed rating announcement is available here: Fitch Upgrades Southern Water's Debt to 'BBB'; Outlook Stable

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

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

Tel:               01903 272 230

Email:           [email protected]

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