Calculate running cost from your settings and rates
Salt-based running cost is primarily a function of regeneration frequency, salt dose, regeneration water and your local prices. The same system can cost different amounts to operate under different hardness, household use and programming. Calculate from those inputs rather than relying on a single annual average.
Separate the four recurring costs
Salt cost equals pounds per regeneration × regenerations per year × delivered price per pound. Water/sewer cost equals regeneration gallons per year ÷ 1,000 × the applicable marginal combined rate per 1,000 gallons. Use your utility's actual billing units and rules; fixed monthly charges usually do not increase because of one regeneration.
Electric controls may consume power, but use the actual model's consumption or measurement if including it. Do not assume a large electric bill simply because a valve uses an outlet. Add planned service, required cleaners or consumables as separate lines.
For a direct buying example, Whirlpool's WHES40 information describes salt compatibility and cleaner-related warranty extension. Requirements like these are model-specific and can change the owner's consumable budget.
An original monthly example
Assume 4.3 regenerations monthly, 6 pounds of salt and 60 gallons of water per regeneration. Assume a delivered 40-pound salt bag costs $8, equivalent to $0.20 per pound, and marginal water/sewer costs $12 per 1,000 gallons. These are illustrative inputs, not observed local prices or a claim about a particular system.
- Salt: 4.3 × 6 = 25.8 pounds; 25.8 × $0.20 = $5.16 monthly.
- Water: 4.3 × 60 = 258 gallons; 258 ÷ 1,000 × $12 = $3.10 monthly.
- Combined illustrated salt/water: about $8.26 monthly, or $99 yearly.
That total excludes electricity, cleaning, delivery fees, repairs and tax. If a salt-delivery service charges separately, include the fee rather than pretending delivered and store-pickup salt prices are identical.
Use efficient capacity consistently
Regeneration frequency should follow working capacity at the selected salt dose, reserve and actual daily load. Do not combine a maximum nominal capacity with a low efficient salt dose unless the performance table supports that pairing. Use salt usage calculator and regeneration frequency to inspect the assumptions.
Track actual bag purchases and regeneration counts for several months. A sharp increase can reflect demand changes, a programming change or a fault; it is a reason to investigate, not automatically proof that resin needs replacement.
Compare other buying models fairly
For a passive conditioner, compare replacement media and cartridges rather than a salt line of zero alone. For rental, read whether service and salt are included, then add excluded consumables to rental payments. Use a common ownership period and keep uncertain inputs visible. Your rates and operating record make the estimate more useful than a national headline number.