Water company performance

Our Water Mark makes it easy for you to access information about your water company's performance.

This is our 2022-23 assessment of how well water companies are performing in the areas that matter most to you.

Water Mark contains information on customers’ views, complaints and operational performance (excel). To demonstrate how well each company has performed, each area has been compared and graded.

Water only companies

Water only companies comparison tabel
Company
Overall service
Value for money
Bills are fair
Bill affordability
Awareness of additional services
Total complaints
Complaints handling measure
Environmental Performance
Annual leakage
Supply interruptions
Average water use
Affinity Water Good Above average Below average Above average Poor Above average Above average N/A Above average Below average Poor
Bristol Water Good Above average Below average Above average Below average Good Above average N/A Good Above average Below average
Cambridge Water Good Above average Below average Good Poor Below average Poor N/A Good Above average Good
Essex and Suffolk Water Good Above average Below average Above average Poor Poor Above average N/A Good Good Poor
Portsmouth Water Good Above average Below average Above average Below average Good Above average N/A Below average Good Poor
SES Water Good Above average Below average Above average Poor Below average Below average N/A Good Good Below average
South East Water Above average Below average Below average Above average Poor Poor Poor N/A Above average Poor Below average
South Staffs Water Good Above average Below average Above average Poor Above average Above average N/A Below average Good Above average

Water and Sewerage companies

Water and sewerage companies comparison table
Company
Overall service
Value for money
Bills are fair
Bill affordability
Awareness of additional services
Total complaints
Complaints handling measure
Environmental Performance
Annual leakage
Internal sewer flooding
External sewer flooding
Supply interruptions
Average water use
Anglian Water Good Above average Below average Above average Poor Above average Below average Below average Good Below average Good Below average Good
Dwr Cymru Welsh Water Good Above average Below average Above average Poor Below average Below average Below average Poor Good Poor Poor Below average
Hafren Dyfrdwy Good Above average Below average Above average Poor Good Above average N/A Poor Above average Below average Below average Below average
Northumbrian Water Good Above average Below average Above average Poor Above average Above average Above average Above average Good Poor Below average Poor
Severn Trent Water Good Above average Below average Above average Poor Good Poor Good Below average Below average Good Above average Good
South West and Bournemouth Water Above average Below average Below average Below average Poor Below average Below average Below average Below average Good Poor Above average Poor
Southern Water Above average Below average Below average Above average Poor Poor Below average Below average Above average Poor Below average Poor Good
Thames Water Above average Above average Below average Above average Poor Poor Poor Below average Poor Below average Above average Poor Above average
United Utilities Good Above average Below average Above average Poor Below average Above average Above average Poor Poor Good Poor Above average
Wessex Water Good Above average Below average Above average Poor Good Above average Below average Below average Above average Above average Good Above average
Yorkshire Water Good Above average Below average Above average Poor Poor Above average Above average Poor Poor Below average Below average Good
Download Download the full Water Mark table (pdf – 195 KB)

Are you unsure who supplies your water?

Enter your postcode on the Water UK website