Guides · Costs
Pool heating cost guide
Pool heating bills are not a single national number. Cost follows how hard weather fights you, how long the heater runs, what fuel you buy, and how much heat you leak at night. Use this guide to think clearly—then estimate with your rates and a pool temperature forecast.
The real cost equation
Roughly:
Cost ≈ energy delivered × price of fuel (or electricity) ÷ effective efficiency
“Energy delivered” is not just nameplate size. It is hours of operation against losses from wind, cold air, evaporation, and your set point. A covered pool in mild weather needs far fewer hours than open water in a cold, dry wind.
Heater types (cost personality)
| Type | Cost personality |
|---|---|
| Gas (NG / propane) | Strong recovery; fuel price and runtime dominate; good for cold snaps and parties |
| Electric resistance | Simple but often expensive per BTU where electricity rates are high |
| Heat pump | Efficient in mild air (COP); weaker / slower when air is cold; electricity still matters |
Get Pool Temp Pro can model these types with your kBTU/h or kW rating, hours or set point, and $/kWh or $/therm. Estimates are planning tools—not a utility bill guarantee.
What moves the bill the most
- Target temperature — each degree above ambient weather costs more to hold
- Cover use — often the highest-ROI “efficiency upgrade” (see cover temperature effects)
- Weather week — wind, cold nights, clouds, and rain increase losses
- Pool volume — more water means more energy to raise temperature (but can hold heat longer)
- Runtime strategy — all-week heating vs event-based heating (see when to heat)
- Your local rates — always beat generic “average US” numbers
Pro tip: Compare cover scenarios with the same heater plan. Lower heat loss usually means fewer heater hours and lower estimated cost over 10 days—even if the heater size stays the same.
How to estimate before you run hard
- Measure current water temp and set a realistic comfort target.
- Forecast weather-only water for 10 days—maybe you need less heat than you think.
- Add your heater type, size, and control mode (hours vs set point).
- Enter your electricity and/or gas rates from a recent bill.
- Toggle cover options and compare estimated hours and cost.
Understanding the water curve itself helps: how pool temperature is predicted.
Ways to cut cost without giving up swimming
- Cover whenever you are not swimming—especially overnight
- Lower the set point a degree or two for weekdays
- Heat for events, not empty afternoons
- Use sun: trim shade only if it is safe and practical; do not ignore trees that matter
- Maintain equipment—dirty filters and low flow waste runtime
FAQ
What is the cheapest way to heat a pool?
The cheapest heat is the heat you do not lose: covers, good sun exposure, and only heating when weather will not hit your target. Among fueled options, heat pumps are often efficient in mild air; gas can be better for quick recovery in cold snaps. Local rates decide the winner.
How much does it cost to heat a pool per day?
It varies widely with heater size, runtime, fuel price, pool volume, weather, and cover use. A small number of hours holding temperature under a cover can cost far less than heating open water through windy nights. Estimate from your rates and planned hours rather than national averages.
Do solar covers reduce heating costs?
Usually yes. By cutting evaporation and overnight losses, covers reduce the hours a heater must run to hold a set point. That often saves more money than tweaking the thermostat by a degree.
Estimate water trend first—then heater hours and cost.
Open free forecast tool