NN5 Northampton
Harder than the UK average. Expect visible limescale on kettles and taps.
At 294 ppm, Northampton sits among the UK's hardest water areas — compare it against the softest areas.
What this means for your home
Based on 294 ppm in Northampton (hard water).
- Significant limescale buildup in kettles, pipes and boilers
- Soap scum on shower screens and taps
- Higher energy bills from scale in heating elements
- Dry skin and dull hair after washing
- White residue on dishes and glassware
Should you soften the water in Northampton?
A verdict and running-cost estimate based on NN5's 294 ppm reading, for a typical 4-person household.
Water is hard to very hard, so appliance, scale and soap savings typically pay back a softener within a few years.
Appliance impact at 294 ppm: noticeable: boiler/dishwasher life cut without descaling. Sized for a 4-person home; regenerates roughly every 9 days (estimate). Figures are conservative estimates and vary with household size and usage.
Hardness data for NN5
Sourced from Anglian Water's published water-quality reports and public records.
Hardness measurements
| Parts per million (ppm CaCO₃) | 294 |
| Degrees Clark (°Clark) | 20.6 |
| Degrees French (°fH) | 29.4 |
| Degrees German (°dH) | 16.5 |
| Calcium (mg/L Ca²⁺) | 118 |
Supplier and area
Read the hard water explainer then use the linked postcode checker to confirm if you are in a hard water area; the region averages very hard.
Other areas near Northampton
Common questions about NN5
What is the water hardness in NN5 Northampton?
Which water company supplies NN5?
Is the water in NN5 safe to drink?
How can I reduce water hardness in NN5?
What does 294 ppm water hardness mean?
What size water softener do I need in NN5?
How much does it cost to run a water softener in NN5?
Fix hard water in Northampton
Enter your email and we will send the limescale fixes that actually work at 294 ppm, plus what to skip.
Check another postcode
Compare hardness across areas before moving or buying a softener.