Thames Water Utilities Limited Half Year Results for the six months to 30 September 2025

Thames Water Utilities Limited (TWUL) today announces its results for the six months to 30 September 2025.

Chris Weston, Chief Executive Officer, said: “The first half of this year has been shaped by good progress across all areas of our operational transformation. We saw a 20% drop in pollutions and leakage performance is holding steady despite the extremely dry summer.

“Financial performance has improved with strong revenue growth, driven by the regulated price rise, good operational expenditure control, resulting in material EBITDA growth.

“We know our infrastructure requires significant investment, and that is why we have launched our Biggest Upgrade in over 150 years to improve our assets and consequently service to our customers and the environment.

“In the first six months of this financial year, we have increased capital investment by 22% to £1.3 billion compared with the same period last year.

“This investment has been funded by higher customer bills, which in turn have led to a rise in customer complaints. In response, we have increased the number of households on our social tariffs to 515,348 and launched a successful pilot that automatically enrols customers in London in financial difficulty for assistance they are entitled to, even if they are unaware of their eligibility.

“This progress has all been achieved as we also manage the recapitalisation of the business. We continue to work closely with stakeholders to secure a market-led solution that we believe is in the best interests of our customers and the environment.

“This in turn will allow the transformation of Thames to continue, a programme that will take at least a decade to complete and will restore the infrastructure and operations of the company.”

Recapitalisation and financial resilience

Significant progress in underlying performance with revenue, EBITDA and operating cashflow all up compared to last year, but our balance sheet remains weak, hence the focus on recapitalising the business.

Our creditors have continued to provide liquidity while the process to agree the terms of recapitalisation with government and regulators is ongoing.

At 30 September 2025, we had drawn £1.43 billion of our £1.5 billion super senior facility, with £872 million on-lent to TWUL.

On 2 October 2025, London & Valley Water (L&VW), a large consortium of Class A Creditors, announced the submission of its proposal to the Company and Ofwat to deliver the turnaround, transformation and recapitalisation of Thames Water without recourse to taxpayers.

Since this submission was made there have been ongoing discussions between the Company, L&VW and Ofwat designed to agree a business plan and capital structure that delivers our required recapitalisation and is supported by a regulatory framework that supports the turnaround of the Company in a way that meets the needs of all our regulators and investors and delivers on our commitments to customers and the environment.

Longer-term, progress requires regulatory reform. We support the Independent Water Commission’s recommendations and continue to work with Defra and our regulators to take this forward.

Key operational highlights

• Significant acceleration in the capital programme in the first half of 2025-26 with £1,260 million of capital invested. Up 22% year-on-year, with investment focused on fixing leaks, pollution and water quality.
• Performance across our six operational priorities:
  • Lost time injuries disappointing in the first two months of the financial year with an improvement since then (HY26: 27; HY25: 20).
  • Compliance Risk Index (CRI), good progress but missed target after a single failure at one of our largest sites (Jan-Sep 25: 3.70; Jan-Sep 24: 1.86). Excluding this, performance would be 1.30.
  • Record first quarter performance for water supply interruptions (HY26: 4 minutes 42 seconds; HY25: 3 minutes 42 seconds), finishing within target despite drought conditions in second quarter leading to twice the usual bursts.
  • Leakage reduction held steady despite the impact of the hottest summer since records began (Three-year rolling average for HY26: 584Ml/d, 13.3% decrease against 2019-20 baseline; HY25: 585 Ml/d, 13.1% decrease against 2019-20 baseline).
  • 20% reduction in pollutions (category 1-3) (Jan-Sep 25: 292; Jan-Sep 24: 364) with 15% more blockages cleared compared to last year and our pipe relining programme ahead of schedule.
  • Complaints increased, driven by the price rise (HY26: 55,158: HY25: 31,600), however water and waste complaints dropped by 11%.
  • At or above sector median performance in 8 of 12 common performance measures and among the top performers in sewer collapses, per capita consumption and leakage in Ofwat’s 2024-25 Company Performance Report despite overall ‘lagging’ rating.
• Rated one out of four stars in the Environment Agency’s 2024 Environmental Performance Assessment, predominantly due to our serious pollution performance and recognition that we were unable to deliver all of WINEP7 in AMP7 (Asset Management Period 7).
• 27% of our energy needs were covered by renewable energy that we generated on our sites (HY25: 24.5%).
• Smart meter installation programme more than doubled in size year-on-year (HY26: 129,082; HY25: 60,984)
• The London Tideway Tunnel Network diverted nearly 3 million cubic metres of sewage from spilling into the River Thames between April and September 2025, totalling over 12 million cubic metres since it went into operation.
• £133 million in affordability support provided in the first half of 2025-26 (HY25: £67 million) and becoming the first water company to automatically enrol customers onto social tariffs, taking the total to 515,348 households.
• 66,838 more households signed up to our Priority Services Register, taking the total to 673,589.

Financial performance

• Underlying revenue up 42% to £1.9 billion, primarily driven by the regulatory uplift in water and wastewater tariffs, enabling the investment necessary to improve our asset resilience, environmental performance and customer experience.
• Underlying EBITDA up 69% to £1.2 billion, primarily due to the increase in revenue but also reflecting tight control of operating costs as we execute the transformation of our business and focus on our priorities.
• Reported profit after tax of £328 million compares with a loss after tax of £190 million in the prior period, driven by the increase in underlying EBITDA combined with significantly lower exceptional costs which together more than offset lower finance income, higher interest costs on our debt and fair value losses on financial instruments.
• Capital investment was up 22% at £1.3 billion over the prior period, driven by the planned step up in investment in our AMP8 Programme to deliver on our broad range of compliance obligations, remedying poor asset performance and progressing strategic investments to secure the future supply of water for our region.
• Liquidity [1] reduced by 44% to £0.9 billion at 30 September 2025, primarily driven by capital investment.
• Senior gearing increased to 85.9% [2] at 30 September 2025, up 1.5 percentage points since 31 March 2025.
• Statutory net debt has increased by 5% to £17.6 billion as at the end of the period since 31 March 2025.

[1] Liquidity is cash and available undrawn debt facilities. As at 30 September 2025 there were no available undrawn debt facilities. Included in this value is £539 million held in TWSSI which is only available to TWUL subject to creditor consent and therefore this cash is not immediately accessible as at 30 September 2025.
[2] Ratio of covenant senior net debt to Regulatory Capital Value (RCV), adjusted for cash in Thames Water Super Senior Issuer plc (TWSSI) unadjusted covenant senior net debt is 88.3% (2024: 84.2%)

• The full Thames Water Utilities Limited Group Interim Report 2025-26 is here.