Calculators / Hot tubs, saunas and plunges
What does a hot tub cost to run?
Put in how warm it is where you live, your tub and your state. You’ll get the monthly electricity cost, three published ways.
Updated · How we check our numbers
At 18.19¢ a kWh
About $34 a month
188 kWh a month for a mid-sized spa in heavy use at a 55°F annual mean (Hot Spring’s tests), about $410 a year.
- Energy
- 188 kWh/mo
- Per year
- $410
- Rate
- 18.19¢ / kWhUS average (EIA)
Estimate for planning only, not professional advice. Check the manufacturer’s instructions, your local code and a licensed professional before you buy, build or install. Use at your own risk. Terms.
Can your deck and panel take it?Weight on the deck and the circuit it needs.
Hot Spring at 55°F → 188 kWh a month
California limit: 3.75 × 350^⅔ + 40 = 226.2 W × (102 − 55) ÷ 37 = 287.4 W
Three published estimates
18.19¢ / kWh- Hot Spring, testedMid-sized spa in heavy use at a 55°F annual mean: 188 kWh a month$34.20/mo
- California’s standby limit350 gal: 226 W at a 37°F difference, 287 W at 55°F; standby only$38.16/mo
- Jacuzzi’s median6 kWh a day across all four seasons$33.18/mo
Energy charges only.
The cover, how hot you keep it and how often you open it matter as much as the climate. Hot Spring’s numbers are for heavy use: six times a week, 30 minutes each.
How we work it out
A hot tub mostly spends energy keeping 102°F water hot against the air around it, so climate matters most. Hot Spring tested a mid-sized spa in heavy use (six times a week, 30 minutes each) in a climate chamber: 100 kWh a month at a 75°F yearly average, 166 at 60°F, 253 at 40°F. We read between those rows for your temperature.
standby limit = 3.75 × gallons^⅔ + 40 watts, at a 37°F water-to-air difference
That's the most standby power California allows a hard-sided spa sold there (7 × gallons^⅔ for inflatables). We scale it by your own temperature difference, as the regulation does, for a ceiling on what a compliant tub uses just sitting with the cover on. Jacuzzi says the median tub uses about 6 kWh a day.
Electricity prices are your state's EIA average, or your own rate. See every state on the electricity cost by state page.
Where the numbers come from
Hot tubs
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