Yorkshire Water supplies most of Sheffield (91.4% of its postcodes), and the quality of that water is regulated by the Drinking Water Inspectorate in England and Wales, per ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries (read 26 September 2026).
Source: ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries — read 26 September 2026Contains OS data © Crown copyright and database right 2026Contains Royal Mail data © Royal Mail copyright and database right 2026Source: Office for National Statistics licensed under the Open Government Licence v.3.0Water company boundaries © Water UK, licensed under CC BY 4.0
Drinking Water Inspectorate (DWI) enforces the UK drinking water quality regulations in England and Wales. Figures it classifies or regulates on this page cover England and Wales only.
The official answer
Sheffield is supplied by Yorkshire Water, whose water is regulated by Drinking Water Inspectorate under the UK drinking water quality regulations.
Source: ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries — read 26 September 2026Contains OS data © Crown copyright and database right 2026Contains Royal Mail data © Royal Mail copyright and database right 2026Source: Office for National Statistics licensed under the Open Government Licence v.3.0Water company boundaries © Water UK, licensed under CC BY 4.0
Who supplies Sheffield
Yorkshire Water's supply area (91.4% of the 11,829 live postcodes in Sheffield): 10813 postcodes
Source: ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries — read 26 September 2026Contains OS data © Crown copyright and database right 2026Contains Royal Mail data © Royal Mail copyright and database right 2026Source: Office for National Statistics licensed under the Open Government Licence v.3.0Water company boundaries © Water UK, licensed under CC BY 4.0
Severn Trent Water's supply area (8.4% of the 11,829 live postcodes in Sheffield): 1004 postcodes
Source: ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries — read 26 September 2026Contains OS data © Crown copyright and database right 2026Contains Royal Mail data © Royal Mail copyright and database right 2026Source: Office for National Statistics licensed under the Open Government Licence v.3.0Water company boundaries © Water UK, licensed under CC BY 4.0
On or near the boundary between Severn Trent Water and Yorkshire Water (0.1% of the 11,829 live postcodes in Sheffield): 12 postcodes
Source: ONS Postcode Directory (May 2026), each postcode placed in the water companies' supply-area boundaries — read 26 September 2026Contains OS data © Crown copyright and database right 2026Contains Royal Mail data © Royal Mail copyright and database right 2026Source: Office for National Statistics licensed under the Open Government Licence v.3.0Water company boundaries © Water UK, licensed under CC BY 4.0
What Yorkshire Water's own figures show
Yorkshire Water's published drinking water quality results for 2023: 166955 published sample results
Source: Yorkshire Water's published drinking water quality results for 2023, published on the water industry's shared data portal — dated 20 September 2026, read 20 September 2026Yorkshire Water Domestic Water Quality 2023 © 2024 by Yorkshire Water is licensed under CC BY 4.0
What an independent test shows
We have not tested Sheffield’s water ourselves. Nothing on this page is our own measurement. You can have your own supply tested.
Related pages
- What we hold on tap-water safety, town by town
- Hard water in the UK
- Check your postcode
- Every zone we hold a figure for
- Yorkshire Water: what we hold
- Yorkshire Water hosepipe ban status
- What Yorkshire Water publishes for your postcode
- UK water companies
- Sheffield, Alabama
- Sheffield, Iowa
- Sheffield, Ohio
- Sheffield, Pennsylvania