Compare the installed price, the drain work included, and five years of salt and regeneration water. Ask both installers to price the same job using your measured water hardness and expected household water use. If one bid leaves the drain route or the operating assumptions blank, ask for a revised quote before comparing totals.
Make sure both quotes solve the same problem
A salt-based ion-exchange softener reduces hardness by exchanging calcium and magnesium for sodium or potassium ions. It uses water and salt to regenerate. The EPA’s WaterSense guidance explains how to compare efficiency; EPA does not give water softeners the WaterSense label. If your concern is a specific contaminant, start with the whole-house versus one-tap filtration guide instead.
Ask for the same five lines on both quotes
| Ask for | What to write down |
|---|---|
| Equipment | Exact model, measured hardness in grains per gallon, and usable capacity at the proposed salt setting. |
| Installation | Which plumbing, bypass valve, drain route, and removal of old equipment are included? |
| Local requirements | Who confirms discharge requirements and handles any necessary permit or inspection? |
| Regeneration | Estimated cycles per month, gallons and pounds of salt per cycle at the proposed setting. |
| Service | Scheduled service cost and separate parts and labor warranty terms. |
Compare five years of cost
This fictional example assumes both models meet the same household need and both quotes cover the same installation work. It uses an assumed marginal water and sewer charge of $10 per 1,000 gallons. Use only variable charges that actually apply to your bill. The example excludes scheduled service, repairs, taxes, financing and future price changes; add any applicable costs to both quotes.
| Cost line | Quote A | Quote B |
|---|---|---|
| Installed price | $1,700 | $2,000 |
| Salt per year | $84 | $60 |
| Regeneration | 30 gallons × 2 cycles/month | 24 gallons × 2 cycles/month |
| Regeneration water per year | 720 gallons / $7.20 | 576 gallons / $5.76 |
| Five-year total | $2,156.00 | $2,328.80 |
Quote B costs $300 more upfront and saves $25.44 a year on the two operating costs shown. Those savings total $127.20 over five years, so Quote A is $172.80 cheaper on these assumptions. Missing scope can reverse the result: if Quote A excludes a $200 drain connection already included in Quote B, Quote A becomes $27.20 more expensive.
To run your own comparison: annual regeneration water in gallons = gallons per cycle × cycles per month × 12. Divide by 1,000 and multiply by your applicable rate per 1,000 gallons. Add annual salt and service, multiply the annual total by five, then add the complete installed price.
Before you sign
Send both contractors the same hardness result and ask for written confirmation of what the quote covers, where the unit will discharge and how they will verify the result after installation. Save both responses with the model data sheets and warranty. For help with the rest of the bid, use Compare Contractor Quotes.
Source checked November 3, 2026: EPA guide to selecting and maintaining a water-efficient softener (May 2026).