Running a hot tub costs most owners between $50 and $150 per month when you add up electricity, chemicals, water, and routine upkeep. Electricity is the biggest chunk, typically $30 to $100 depending on your local rate, your climate, and how well-insulated your tub is. Chemicals run $20 to $50 a month for most people. The rest – water, filter replacements, and the occasional service call – fills in the gap. Here is exactly where your money is going and how to keep that number on the low end.
Why the range is so wide: what actually drives hot tub costs
The difference between a $55-a-month hot tub and a $150-a-month hot tub comes down to a handful of factors: the age and insulation quality of the tub, the condition of the cover, your local electricity rate, your climate, and how often you use it. A 10-year-old tub with a waterlogged cover sitting in Minnesota winters will cost dramatically more to run than a modern energy-efficient tub in Georgia with a tight-fitting cover. Usage also matters – running the jets hard for an hour daily costs more than a few quick soaks a week.
If you want a deeper look at how these numbers stack up in practice, the Hot Tub Running Costs: A Real Monthly Breakdown on this site goes line by line through a real tub owner’s monthly expenses. It is a useful companion to what you are reading now.
How much electricity does a hot tub use per month?
A typical hot tub draws between 1,500 and 6,000 watts when the heater and jets are running. In normal operation – holding temperature with occasional jet use – most 220V hot tubs consume 150 to 400 kWh per month. At the U.S. average electricity rate of about $0.16 per kWh, that works out to roughly $24 to $64 per month. If you live somewhere cold or your electricity rate is higher (California and New England often see $0.25 to $0.35 per kWh), that number climbs fast.
The single biggest thing you can do to lower your electricity bill is fix your cover. A waterlogged, cracked, or poorly fitting cover leaks heat constantly, forcing the heater to run more than it should. A good cover in good condition can cut heating costs by 30 to 50 percent. That is not a small number. River Pools and Spas has written about cover insulation and its impact on total ownership costs, and the math is consistently convincing: a $300 cover replacement often pays for itself in under a year through energy savings.
What do hot tub chemicals cost per month?
Plan on spending $20 to $50 per month on chemicals if you are maintaining your water consistently. Here is how that typically breaks down:
- Sanitizer (chlorine or bromine): $10 to $20 per month for a moderately used tub
- pH and alkalinity adjusters: $5 to $10 per month depending on your source water
- Shock: $5 to $15 per month, more if you have heavy usage weeks
- Calcium hardness increaser: Usually a one-time-ish cost every few months, $5 to $10
Owners who let their water go out of balance tend to spend significantly more – not because the chemicals are expensive, but because they end up buying corrective products on top of their regular routine. Staying on top of testing twice a week keeps chemical costs predictable. AquaDoc makes a simple all-in-one chemical kit for hot tub owners that covers the basics without making you buy a dozen separate products – worth mentioning if you are tired of figuring out what to stock.
Water and filter costs: the easy ones to forget
Hot tubs need fresh water every 3 to 4 months for most owners, depending on bather load and how well the chemistry has been maintained. Draining and refilling a 350 to 500 gallon hot tub costs under $5 in water and sewer fees for most households. Not a big deal, but worth factoring in.
Filters are the other easy-to-forget cost. A quality replacement filter for most hot tubs runs $20 to $60. Most manufacturers recommend replacing filters every 12 to 24 months, though if you are cleaning them monthly and the media looks degraded, replace sooner. Prorating a $40 filter over 18 months is about $2.25 per month – cheap insurance against cloudy water and pump strain.
Annual and occasional costs broken down monthly
Some costs hit once a year or less but are still part of owning a hot tub. When you average them into a monthly figure, the picture gets a little more complete:
- Annual professional service/inspection: $100 to $200 per year, or about $8 to $17 per month
- Filter replacement: $20 to $60 per year, about $2 to $5 per month
- Cover replacement (every 5-7 years): $300 to $600, or $4 to $10 per month averaged out
- Unexpected repairs: Hard to predict, but budget $15 to $25 per month as a reserve
Add those to your electricity and chemical costs and a realistic all-in monthly number for most owners lands between $80 and $175. The lower end is achievable with a newer, well-insulated tub, a good cover, and consistent chemical maintenance. The higher end is what you get if any of those things slip.
How to actually lower your monthly hot tub costs
If your bill feels high, work through this list before assuming something is broken:
- Check your cover for waterlogging – press down on it and see if water squishes out. A saturated cover is an energy sieve.
- Lower your set temperature by 2 to 3 degrees. Each degree of setpoint reduction saves roughly 10 percent on heating energy.
- Use the tub’s economy or sleep mode during hours you never soak, typically late night to early morning.
- Test your water twice a week and dose correctly – catching a pH problem early is far cheaper than treating the aftermath.
- Clean your filters monthly with a garden hose and a filter cleaner spray. Clogged filters make the pump and heater work harder.
One underrated move: add a floating thermal blanket under your cover. These cost $20 to $40 and add a meaningful extra layer of insulation between the water surface and the cover. Combined with a tight cover, they can shave $10 to $20 off your monthly electric bill.
Frequently Asked Questions
How much does it cost to run a hot tub per month?
Most hot tub owners spend between $50 and $150 per month on electricity, chemicals, water, and routine maintenance. Electricity is usually the biggest single expense, typically $30 to $100 depending on your rate, climate, and how well-insulated your tub is.
How much does a hot tub raise your electric bill?
A hot tub typically adds $30 to $100 to your monthly electric bill. Older or poorly insulated tubs lean toward the high end; newer energy-efficient models with good covers stay closer to $30 to $50 per month.
How much should I budget for hot tub chemicals per month?
Plan on $20 to $50 per month for hot tub chemicals if you are maintaining your water correctly. Owners who let their water drift out of balance often spend more because they are buying corrective chemicals on top of their usual sanitizer and balancers.
Is it cheaper to leave a hot tub on all the time?
Yes. Keeping your hot tub at temperature continuously is cheaper than letting it cool down and reheating it. Reheating from cold uses significantly more energy than maintaining a set temperature, especially in cold climates.
What is the most expensive part of running a hot tub?
Electricity is almost always the biggest ongoing cost, accounting for roughly half to two-thirds of your total monthly hot tub expense. A failing or thin cover is the single biggest driver of high electricity bills because heat escapes constantly.
The bottom line: a hot tub does not have to be an expensive appliance to run. Most of the people paying $150-plus a month are doing so because of a cover problem, a temperature setting they never adjusted, or chemistry that keeps getting ahead of them. Fix those three things and you will likely land in the $60 to $90 range – which, spread across however many soaks you get per month, is a pretty reasonable number for what a good hot tub actually delivers.