Water Charges

Where ADSM acts as your water retailer (England) or licensed provider (Scotland), charges are generally made up of:

1. Wholesale charges – set by your regional wholesaler.
2. Retail charges – applied by ADSM for customer services and account management.

Wholesale Charges

To identify your wholesaler, please use the Water UK supplier lookup service:
Find your supplier

Please select your wholesaler from the list below to view the applicable wholesale scheme of charges

2026-2027

• Affinity Water
• Anglian Water
• Bristol Water
• Dee Valley Water
• Dŵr Cymru
• Northumbrian Water
• Portsmouth Water
• Scottish Water
• Severn Water
• Southeast Water
• Southern Water
• South Staffs Water
• Southwest Water
• Southwest Water (Bournemouth)
• Southwest Water (Special Agreements)
• Sutton Water
• Thames Water
• United Utilities
• Wessex Water
• Yorkshire Water

Retail Charges

Contract Customers

If you are on a contract tariff, wholesale charges will be increased by the fixed retail markup percentage agreed within your contract. Where the contract was arranged through a framework agreement, ADSM may use part of this markup to cover framework fees. The retail markup percentage will be clearly stated within your contract documents.

Default Rate Customers

For customers who are not under a signed contract, where a deemed contract applies, we apply retail charges in line with Ofwat’s Retail Exit Code‘s allowed charges.

Customer charges are determined according to annual water consumption:

Group One Customers

We are permitted to charge a fixed fee (allowed cost to serve) plus an additional charge for metered supplies (metered services fee), plus a % markup (which combines a retail net margin and a customer bad debt allowance). Ofwat present this as:

Total payable per service = ([Wholesale cost] + [Allowed Cost to Serve] + [Metered Services Fee]) / ( 1 – [Retail Net margin %] – [Bad Debt Allowance %])

The current values for 2026-2027 are:

• [Allowed Cost to Serve]: £56.09
• [Metered Services Fee]: £10.93 (metered supplies only)
• [Retail Net Margin %]: 2.00%
• [Bad Debt Allowance %]: 2.45%

Group Two Customers

The retail fee is a percentage of the wholesale charges.

• Water services: 8.0%
• Sewerage Services: 10.0%

Total payable = [Wholesale cost] * ( 1 + [margin %])

Group Three Customers

• The charges payable by the Eligible Exit Area Customer are reasonable; and
• There is no undue preference shown to, and that there is no undue discrimination against, any Eligible Exit Area Customer compared with the Licensee’s other Customers of the same class as the Eligible Exit Area Customer.