Are you wondering about the hardness of your water?
Understanding whether your water is soft, hard, or somewhere in between can help you make better decisions about water usage, appliance care, and even your health. This guide will walk you through everything you need to know about water hardness, how to find out the hardness in your area, and how to access resources for accurate measurements.
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Check your water hardness by postcode
Enter your postcode for an instant estimate of your local water hardness, your likely supplier, and what it means for your home.
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Results are estimated regional averages by postcode area, compiled from published water company hardness data and are not property-specific — supply zones can vary within a region. For an exact reading, check the supplier links further down this page.
What Is Water Hardness?
Water hardness refers to the concentration of minerals, primarily calcium and magnesium, in your water. It’s measured in milligrams per litre (mg/L) as calcium carbonate (CaCO₃). Here’s how hardness is classified:
- Soft water: 0–50 mg/L
- Moderately soft water: 51–100 mg/L
- Slightly hard water: 101–150 mg/L
- Moderately hard water: 151–200 mg/L
- Hard water: 201–300 mg/L
- Very hard water: Over 300 mg/L
The hardness of your water can vary based on location. Use the resources below to check the hardness level in your area.
How to Check Your Water Hardness
Several water providers in the UK offer detailed hardness data. Simply use the links below to search for your area:
Why Does Water Hardness Matter?
Hard water contains minerals that can leave behind scale build-up in kettles, pipes, and household appliances. While these minerals are harmless to health, they can reduce the efficiency of appliances, increase energy costs, and require additional maintenance.
On the other hand, soft water can be corrosive to pipes and may not provide the same cardiovascular benefits associated with calcium and magnesium in hard water.
How to Manage Water Hardness
If you live in a hard water area, here are some tips:
- Use a water softener: These devices reduce hardness by replacing calcium and magnesium with sodium.
- Install descaling systems: Magnetic and electronic devices can help minimize scale build-up.
- Consult your water provider: Use the links above to access specific recommendations for your region.