Direct answer: North Star does not publish prices. It sells only to plumbers, contractors and water-treatment professionals, so the cost of a North Star softener is whatever an installer quotes for the equipment and installation together. What the manuals do document is the running cost: the NSC22, NSC31 and NSC42 are rated at 4,474, 5,090 and 4,940 grains of hardness removed per pound of salt at their minimum doses, use 30.4 to 45.9 gallons of water per full-dose regeneration, and need no proprietary cleaner to keep their warranty. Real-world salt efficiency is “typically less” than the rating.
Publisher boundary: Water System Guide is an independent research publisher, not a North Star dealer. This page uses manual 7393624 (NSC22 and NSC31) and manual 7393632 (NSC42), both Rev. H dated January 7, 2026, and northstarwater.com, reviewed October 15, 2026. Calculations are our arithmetic and are labeled. We do not quote equipment or installation prices because none are published by the manufacturer.
Why there is no list price
The North Star residential softeners page describes the company as “an equipment supplier that distributes exclusively to plumbers, contractors and industry professionals.” There is no cart or price on the manufacturer’s site. Homeowners find an installer through the servicer locator, which searches by ZIP code.
That means two quotes for the same model can differ a lot, because each bundles equipment markup, labor, fittings, drain work and sometimes water testing. For typical installed-cost ranges across brands, see our water softener cost guide.
What a North Star quote should spell out
Ask for these items in writing so quotes can be compared:
- Exact model and part number, for example NSC31 (part NSC3123). Our North Star models comparison lists the differences.
- Measured hardness and iron from a test of your untreated water, and the hardness number the installer will program.
- Bypass, connection and drain work. The softener ships with a bypass valve; ask what else is included.
- Pressure-reducing valve if daytime pressure exceeds 80 psi. The manual says nighttime pressure may then exceed the 125 psi maximum, and that failure to use one “may cause damage to the system, resulting in flooding and damage to property” (NSC31 manual, PDF page 4).
- Expansion tank if the home has a backflow preventer, as local codes require.
- Labor coverage. The manual’s warranty covers parts and gives no labor term. Ask what the contractor covers and for how long.
- Who handles warranty claims. The warranty sends owners to the contractor first.
Salt: the main running cost
Rated capacities at three salt doses come from the specification tables (NSC22/NSC31 manual, PDF page 3; NSC42 manual, PDF page 3). Dividing capacity by salt is our arithmetic:
| Dose point | NSC22 | NSC31 | NSC42 |
|---|---|---|---|
| Lowest | 8,700 at 1.9 lbs. (about 4,580/lb.) | 12,300 at 2.4 lbs. (about 5,125/lb.) | 12,400 at 2.5 lbs. (about 4,960/lb.) |
| Middle | 18,500 at 6.2 lbs. (about 2,985/lb.) | 26,200 at 7.7 lbs. (about 3,400/lb.) | 33,300 at 9.5 lbs. (about 3,505/lb.) |
| Highest | 22,100 at 10.4 lbs. (about 2,125/lb.) | 31,300 at 12.9 lbs. (about 2,425/lb.) | 42,100 at 16.3 lbs. (about 2,585/lb.) |
| Manual’s rated efficiency | 4,474 at 1.9 lbs. | 5,090 at 2.4 lbs. | 4,940 at 2.5 lbs. |
Our simple division differs slightly from the rated efficiencies because of how the rating test is calculated; use the manual’s figures for comparisons. The manuals warn that operational efficiency “is typically less than the rated efficiency, due to individual application factors including water hardness, water usage, and other contaminants.”
The Salt Efficiency setting keeps the softener at 4,000 grains per pound or better by regenerating more often with smaller doses. It ships OFF and must be ON in California. The 97% feature can also “save salt and water” by regenerating when 97% of capacity is used, at any time of day. Both are explained in our North Star regeneration guide.
Estimate your salt use
- Grains per day = hardness (gpg) x gallons per day. Add 5 gpg for each 1 ppm of clear-water iron, as the manuals’ hardness setting does.
- Pounds per day = grains per day / grains per pound.
Example (our arithmetic, not a manufacturer figure): 250 gallons a day of 15 gpg water is 3,750 grains a day. At the NSC31’s rated 5,090 grains per pound, that is about 0.74 pounds of salt a day, roughly 22 pounds a month. At a more conservative 3,000 grains per pound, it is 1.25 pounds a day.
The NSC42 can give you the gallons figure directly. Pressing its WATER USE button shows the current flow rate; pressing it a second time shows the average gallons of soft water the household uses each day, recalculated daily (NSC42 manual, PDF page 17).
Water used in regeneration
| Water use | NSC22 | NSC31 | NSC42 |
|---|---|---|---|
| At minimum salt dose | 3.0 gal. per 1,000 grains | 2.5 gal. per 1,000 grains | 2.5 gal. per 1,000 grains |
| Per regeneration at maximum dose | 30.4 gallons | 31.1 gallons | 45.9 gallons |
Example (our arithmetic): the 3,750-grain-a-day household would send about 9.4 gallons a day to the drain on an NSC31 at the minimum-dose rate. The optional Clean feature adds a backwash and rinse to each regeneration; the manual says to keep it OFF unless the water has iron or sediment.
Electricity
All three run on a 24V DC plug-in power supply connected to a grounded, protected 120V, 60 Hz outlet in a dry location, and the installation steps call for an outlet that is not controlled by a switch (NSC31 manual, PDF page 4). The manuals give no wattage or annual electricity figure, and we have not measured one.
Warranty costs: no cleaner requirement
The North Star warranty in both manuals has three terms: one year on all parts, five years on the electronic control board and valve body, and ten years on the salt storage tank and fiberglass resin tank, all from the delivery date. Defective parts in those periods are shipped to the home free (NSC31 manual, PDF page 28).
The five-year board-and-valve term is longer than the three-year electronic control board term in the January 2026 Rheem RHS32 manual, a retail softener from the same manufacturer, Water Channel Partners. The tank terms are the same ten years.
Unlike some retail softeners, the reviewed North Star warranty does not require a branded cleaner or additive to keep coverage. It does exclude failure to “perform any preventive maintenance,” normal wear and tear, improper installation and aftermarket parts. Labor is not mentioned, so it falls to the contractor’s own terms. Our North Star parts guide lists order numbers for parts you may pay for after the warranty ends.
Does a bigger North Star cost more to run?
Not per grain. The NSC31 has the best rated efficiency of the three at its minimum dose, 5,090 grains per pound, against 4,940 for the NSC42 and 4,474 for the NSC22. The NSC22 also uses more water at its minimum dose, 3.0 gallons per 1,000 grains against 2.5 for the other two.
Size changes how often the softener regenerates and what water it can handle. The specification tables list maximum supply hardness of 95 gpg for the NSC22, 110 for the NSC31 and 120 for the NSC42, and maximum clear-water iron of 6, 8 and 11 ppm. Rated service flow is 7.2 gpm for the NSC22 and NSC31 and 9.9 gpm for the NSC42. The NSC42’s larger resin bed holds more capacity between regenerations but uses 45.9 gallons per full-dose regeneration against about 31 for the smaller two. Because the tables show salt efficiency falling as the dose rises, a softener that must run near its highest dose to keep up will use more salt per grain removed. Size it from a water test rather than from price.
Costs that come from the water, not the softener
Some extra costs show up only after a water test. The manuals say the softener will not remove sediment, and that “a sediment filter installed upstream of the water softener normally corrects this situation.” They also say it will not remove ferric (red-water), bacterial or colloidal iron (NSC31 manual, PDF page 5). Water that is “microbiologically unsafe or of unknown quality” needs disinfection before or after the softener. If a test shows any of these, expect the quote to include additional equipment, and ask the installer to explain why each item is needed.
Frequently asked questions
How much does a North Star water softener cost?
North Star does not publish prices. It sells only through plumbers and contractors, so the price comes from an installer’s quote that includes equipment and installation.
Where can I buy a North Star water softener?
From a plumber or water-treatment contractor that carries the brand. North Star’s servicer locator on northstarwater.com searches by ZIP code.
How much salt does a North Star softener use?
It depends on hardness and water use. The manuals rate the NSC22, NSC31 and NSC42 at 4,474, 5,090 and 4,940 grains per pound of salt at their minimum doses, and say real-world efficiency is typically lower.
Does the North Star warranty require a special cleaner?
The reviewed NSC22, NSC31 and NSC42 warranties do not require a branded cleaner. They exclude failure to perform preventive maintenance, improper installation and aftermarket parts.