How Much Does It Cost to Heat a Pool in Las Vegas?

A single warm-up of a typical Las Vegas pool takes roughly 45 therms of natural gas, or about $25 to $45 of electricity with a heat pump at NV Energy’s current rate of about 11.5 cents per kWh. Keeping it warm every day is where the cost climbs, because an uncovered pool dumps most of that heat overnight. A cover cuts heating costs by 50% to 70%, according to the U.S. Department of Energy.

Why are people asking about this right now?

Because the water is dropping fast.

In September your pool was bathwater. By Thanksgiving (Nov. 26 this year), a lot of Henderson and Las Vegas pools sit in the 50s. December normals at Harry Reid Airport run highs of 56 to 60 degrees and lows of 39 to 42, per the National Weather Service.

So the kids want a holiday swim, the in-laws are coming, and somebody asks the big question. “What would it cost to just turn the heater on?”

There’s a little good news on the bill side, too. NV Energy’s quarterly adjustment on Oct. 1, 2026 lowered the average single-family residential bill about 3.6%, or about $5 a month.

How much heat does a Las Vegas pool actually need?

Let’s use a real local pool. The Southern Nevada Water Authority says a typical pool here is about 470 square feet. At an average depth of 5 feet, that’s roughly 17,500 gallons.

Water takes about 8.34 BTUs to warm one gallon by one degree. Raising 17,500 gallons from 58 to 84 degrees (a 26-degree jump) takes about 3.8 million BTUs.

That’s the number everything else hangs on.

And it’s the best case. It assumes the pool holds every bit of heat while it warms up, which it won’t on a breezy 45-degree night.

What does it cost with a gas heater?

Natural gas is sold by the therm, and one therm is 100,000 BTUs. Most newer gas pool heaters run about 80% to 95% efficient, per the DOE.

At 84% efficiency, our 3.8 million BTU warm-up burns about 45 therms. Multiply that by the per-therm price on your Southwest Gas bill and you have your one-time number.

Gas has one big advantage. Speed.

A 400,000 BTU heater can do that warm-up in about 11 to 12 hours of run time. Fire it up Wednesday night, swim Thursday afternoon. That’s why gas makes sense for families who swim a handful of times in winter.

What does it cost with a heat pump?

A heat pump pulls heat out of the air and moves it into the water. The DOE puts their efficiency (called COP) at about 3.0 to 7.0, meaning every unit of electricity you pay for moves 3 to 7 units of heat.

Our 3.8 million BTUs equals about 1,112 kWh of heat. Here’s the electric cost at NV Energy’s Oct. 1 single-family rate of about $0.115 per kWh:

• COP 5: about 222 kWh, roughly $26
• COP 4: about 278 kWh, roughly $32
• COP 3: about 371 kWh, roughly $43

Cheap, right? Here’s the catch.

The DOE says heat pumps work efficiently as long as the air stays above about 45 to 50 degrees. Vegas winter nights dip below that a lot. So your heat pump does great on a 62-degree December afternoon and struggles at 2 a.m. A typical 125,000 BTU unit would need around 30 hours of run time for this warm-up, and longer when it’s cold out.

Heat pumps shine in spring and fall, and for people who want to stretch the season. They’re slower for a last-minute January swim. Your pool won’t be ready in an hour. It barely gets ready in a day.

Why does keeping it warm cost so much more?

Evaporation. The DOE calls it “by far the largest source of energy loss” in a pool.

Las Vegas is basically built for evaporation. Dry air, wind, and that big open surface. SNWA says an average pool here loses about 48.6 gallons of water per square foot every year, or close to 22,800 gallons for a 470-square-foot pool. Every gallon that evaporates takes heat with it.

So if you warm the pool on Friday and leave it uncovered, you’re paying to heat the desert sky by Sunday.

Your heater isn’t broken. It’s just heating Nevada.

Does a pool cover really make that big a difference?

Yes. This is the cheapest fix on the list.

SNWA says a cover cuts evaporation by 90%. The DOE says a cover can save 50% to 70% on heating costs. Look at the DOE’s own heat pump example for a 1,000-square-foot pool kept at 80 degrees in Phoenix: about $1,192 a season uncovered, versus about $116 covered.

A basic solar bubble cover is the lowest-cost option, per the DOE. If you only heat for weekends and holidays, cover it the minute you get out.

Does hard water affect my heater?

It does, and it’s a big one here.

Our water in the valley is hard, and a pool concentrates calcium as it evaporates. The DOE notes that scale buildup in a heater’s burner or heat exchanger can reduce efficiency over time. A heater full of scale burns more gas or electricity for the same warm-up, and it’s one of the most common reasons we see heaters quit early.

Keeping your calcium, pH and alkalinity balanced every week is what protects that heat exchanger. That’s part of what our weekly service covers.

So, gas or heat pump?

Here’s how we’d think about it:

• Swim a few times a winter, need it warm fast? Gas.
• Want to stretch swim season into November and start in March? Heat pump.
• Either one? Use a cover, or you’re throwing money over the block wall.

Not sure if your heater even works? Fire it up now, not on Thanksgiving morning.

Want us to check your heater before the holidays?

We service pools all over Henderson and Las Vegas. We can test your heater, check it for scale, balance your water so it doesn’t build back up, and give you a straight answer on repair versus replace.

Call or text Summit Pool Services at (702) 608-5226. We’re open 24/7.