Thames Wat.u 35 Regulatory News (AW14)

Thames Water Utilities Limited

27 August 2025

Investigations Update - Payment Plan

Thames Water Utilities Limited (the "Company") has agreed a payment plan with Ofwat relating to penalties issued on 28 May 2025 in relation to its wastewater business (£104.5m) and in relation to dividend payments (£18.2m).

The penalty payment plan will see 20% of the total combined penalties paid no later than 30 September 2025, a sum of £24.5m.

The balance will be paid on the earliest of three possible events, as set out by Ofwat:

· 30 calendar days after the implementation of the company's restructuring plan;

· 31 March 2030;

· If the company enters the Special Administration Regime (SAR) under the Water Industry Act 1991, 30 calendar days after it exits SAR;

These penalties will not be funded by customer bills.

The Company continues to work closely with stakeholders to secure a market-led recapitalisation which delivers for customers and the environment as soon as practicable.

For further information

Investor enquiries

Frederick Maroudas - Director of Corporate Finance debt.investorrelations@thameswater.co.uk

Media enquiries

Suvra Jans - Head of Media Relations suvra.jans@thameswater.co.uk M: 07747 640 810

LEI: 213800JKM5UQHFJOTZ25

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