What is the water hardness in Harrow?

Between 256 and 271 mg/L depending on the district, with a median of 264. The hardest measured district is HA1 at 271 mg/L and the softest is HA8 at 256. Figures come from water company drinking-water tests.

Do I need a water softener in Harrow?

In most HA homes a softener pays for itself: at 264 mg/L kettles, boilers and showers scale up quickly. Check your own district first, because hardness varies from 256 to 271 within the area.

Is Harrow a hard water area?

Yes. Tap water across the HA postcode area is very hard, the top band on the scale water companies use, with a median of 264 mg/L calcium carbonate. It ranges from 256 mg/L in HA8 to 271 mg/L in HA1, from 10 districts with their own water company reading.

Soft
Moderately soft
Slightly hard
Hard
Very hard

Hardness in mg/L as calcium carbonate, the scale UK water companies report in.

Hardness by HA district

Hardest first. Hard starts at 180 mg/L, very hard at 250.

District	Area	mg/L	Hardness
HA1	Harrow	271	very hard
HA0	Brent	269	very hard
HA6	Hillingdon	268	very hard
HA2	Harrow	266	very hard
HA9	Brent	264	very hard
HA4	Hillingdon	264	very hard
HA5	Harrow	259	very hard
HA7	Harrow	258	very hard
HA3	Harrow	257	very hard
HA8	Barnet	256	very hard

Softener quotes for Harrow

At 264 mg/L most HA homes get their money back on a softener within a few years. Free quotes from installers covering your postcode, no obligation.

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Check your exact postcode

The area figure is a median. Your district can sit anywhere between 256 and 271 mg/L.

Nearby areas

Is Harrow a hard water area?: Yes. The median hardness across HA postcode districts is 264 mg/L calcium carbonate, which is very hard. 100% of the 10 districts we hold readings for are hard or very hard (180 mg/L and above).
What is the water hardness in Harrow?: Between 256 and 271 mg/L depending on the district, with a median of 264. The hardest measured district is HA1 at 271 mg/L and the softest is HA8 at 256. Figures come from water company drinking-water tests.
Do I need a water softener in Harrow?: In most HA homes a softener pays for itself: at 264 mg/L kettles, boilers and showers scale up quickly. Check your own district first, because hardness varies from 256 to 271 within the area.

Hardness as mg/L calcium carbonate from water company drinking-water tests and postcode checkers. See the UK hardness map for every area.