Updated August 15, 2026 · WattCostLab Calculator
Hot Tub Electricity Cost Calculator
Estimate the electricity cost of a hot tub using heater power, estimated heater runtime, circulation load and your local electricity rate.
Daily energy: —
Monthly cost: —
Annual cost: —
Formula
Estimated daily energy = heater power × heater runtime + circulation/standby energy. Monthly cost = daily energy × 30.4 × electricity rate.
Why actual hot tub energy use varies
- Outdoor temperature and wind exposure.
- Water setpoint.
- Cover insulation and condition.
- Frequency and duration of use.
- Heater and pump efficiency.
- Filtration and circulation schedule.
- Tub size and heat loss from plumbing.
How to get a better estimate
If you have a dedicated energy monitor or utility interval data, use measured kWh rather than assumed heater runtime. The calculator is most useful for scenario comparison: for example, comparing different electricity rates, heater runtimes or insulation improvements.
Related calculators
Try the Electricity Cost Calculator, Electricity Usage Calculator and Electricity Bill Calculator.
Estimate only: Actual hot tub electricity use depends strongly on weather, insulation, controls and user behavior.