WaterWater Hardness by UK Region
Compare water hardness across 10 UK regions, ranked by average hardness.
East Of England
203 postcodes Very Hard
London
330 postcodes Hard
South East
352 postcodes Hard
East Midlands
106 postcodes Hard
West Midlands
203 postcodes Hard
Yorkshire
217 postcodes Hard
South West
278 postcodes Moderately Hard
North East
122 postcodes Slightly Hard
North West
270 postcodes Slightly Hard
Wales
205 postcodes Slightly Hard
How Water Hardness Varies by Region
Water hardness in the UK varies dramatically by region due to underlying geology. The South East and East of England have the hardest water, with chalk and limestone aquifers dissolving calcium carbonate into the supply. Scotland and Wales have the softest water, drawn from granite and peat-based sources.
Learn more about what causes water hardness or check your specific postcode.