Breakdown of water companies’ bill increases 2025-30

The tables show the year-by-year increases in water and sewerage bills as proposed in Ofwat’s draft determinations. These figures do not take into account inflation which water companies are allowed to add to customers’ bills every year.

Water and sewerage companies

The combined bill represents the total of the water bill and the sewerage bill.

‘For customers of two of these companies, simply add the water bill from your water supplier to the sewerage bill from your wastewater supplier

Anglian Water

Dŵr Cymru

Hafren Dyfrdwy

Northumbrian Water

Severn Trent Water

South West Water

Southern Water

Thames Water

United Utilities

Wessex Water

Yorkshire Water

Water only companies

To calculate the total bill, simply add the water bill from the water supplier to the sewerage bill from the wastewater supplier.

The figures reflect the revenue Ofwat proposes to allow each company to collect for water and wastewater activities, respectively. Ofwat also sets revenue allowances for retail activities. The retail allowance per customer has been split half to water and half to wastewater.

Each revenue allowance has been divided by the forecast number of household customers to produce an average bill figure. For water and wastewater companies, retail allowances have been divided by the number of water and wastewater service customers.