Water softener cost
A water softener costs $800 to $3,500 installed, typically $1,800. Before spending anything, test your hardness. Below about 7 grains a softener solves a problem you do not have.
National average
$1,800
per project
On this page
A water softener costs $800 to $3,500 installed, typically around $1,800. The unit is half of that; the rest is the plumbing to tie it into the main and the drain it needs for regeneration.
Before spending anything, find out how hard your water actually is. A $15 test kit or a free report from your utility answers it, and a fair number of people install softeners for water that did not need it.
What it costs
| Type | Installed cost |
|---|---|
| Ion exchange softener, single tank | $800 to $2,500 |
| Ion exchange, dual tank for continuous supply | $1,500 to $3,500 |
| Salt-free conditioner | $800 to $3,000 |
| Magnetic or electronic descaler | $200 to $600 |
| Whole-house filter added alongside | $300 to $1,200 |
| Reverse osmosis at the kitchen tap | $250 to $900 |
| Plumbing tie-in and bypass valve | $300 to $900 |
| Drain line and air gap | $150 to $500 |
| Adding a socket at the unit | $150 to $400 |
| Salt, per year | $50 to $150 |
When you need one
Hardness is measured in grains per gallon or parts per million.
| Hardness | Grains per gallon | Worth softening |
|---|---|---|
| Soft | 0 to 3 | No |
| Slightly hard | 3 to 7 | Rarely |
| Moderately hard | 7 to 10 | Sometimes |
| Hard | 10 to 14 | Usually |
| Very hard | 14 and above | Yes |
Above about 10 grains, scale genuinely shortens the life of a water heater, clogs fixture aerators, leaves spots on everything and makes soap work badly. Below 7, a softener is solving a problem you do not have.
The honest saving is in equipment life and detergent, not in the water bill. A water heater in very hard water can lose a third of its life to scale, and that is a real number: $1,500 of heater over fifteen years.
Ion exchange, salt-free, and the ones that do nothing
Ion exchange is a real softener. It swaps calcium and magnesium for sodium on a resin bed and periodically regenerates using salt. It genuinely removes hardness, and it is the only type that does. It needs salt, a drain, and it adds a small amount of sodium to the water.
Salt-free conditioners do not remove hardness. They change the crystal structure so scale is less likely to stick to surfaces. They work for scale prevention in pipes and heaters, they do nothing for soap performance or spotting, and calling them softeners is a marketing decision rather than a technical one. They need no salt and no drain, which genuinely suits some houses.
Magnetic and electronic descalers have no credible independent evidence behind them. Save the money.
Sizing and the mistake people make
Grain capacity should match household size times daily use times hardness. A rough rule: four people, 75 gallons each a day, at 15 grains, is 4,500 grains a day, and a 32,000 grain unit regenerating roughly weekly is right.
The mistake is oversizing on the theory that bigger regenerates less often. A softener that sits for two weeks between regenerations grows bacteria in the resin bed. Sized correctly it regenerates every three to seven days, which is what it is designed to do.
Frequently asked questions
Is softened water safe to drink?
Yes for almost everyone. It adds sodium in proportion to the hardness removed — roughly 30 mg per litre at 10 grains, which is less than a slice of bread. Anyone on a strictly sodium-restricted diet should either use potassium chloride instead of salt, or leave the kitchen cold tap unsoftened, which most installers will do on request.
Will it fix my rotten egg smell or my orange stains?
No. Sulphur smell and iron staining are different problems needing different equipment. A softener removes a little iron incidentally and is not the fix. Get the water tested properly before buying anything.
How long do they last?
Ten to twenty years for the resin and the valve head. The control valve is usually what fails first and is often replaceable on its own.
Can I install one myself?
If you are comfortable cutting into the main supply, fitting a bypass valve and running a drain line to a proper air gap, yes. The air gap matters: a drain line pushed into a standpipe without one can back-siphon.
Do I still need a filter?
A softener is not a filter. It removes hardness, not sediment, chlorine, lead or bacteria. If you want better drinking water, that is a separate reverse osmosis unit at the kitchen tap for $250 to $900.
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