South West Water supplies most of Bristol (99.9% 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
Bristol is supplied by South West 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 Bristol
South West Water's supply area (99.9% of the 11,735 live postcodes in Bristol, City of): 11731 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
Not placed in any regional water company's supply area (under 0.1% of the 11,735 live postcodes in Bristol, City of): 4 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 South West Water publishes for the Bristol Water area
South West Water publishes the Bristol Water area on the water industry's shared data portal as a region of its own, in 3 annual performance reports, and none of its 4 drinking-water-quality datasets there is published for that area (read 20 September 2026). Their company-wide sample counts are therefore not printed here as Bristol's.
Source: the Stream ArcGIS organisation — every service it publishes, enumerated — dated 20 September 2026, read 20 September 2026
What an independent test shows
We have not tested Bristol’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
- South West Water: what we hold
- South West Water hosepipe ban status
- What South West Water publishes for your postcode
- UK water companies
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