Heat Pump vs Gas Pool Heater: Which Saves More Money in 2025?

Ever stared at your monthly energy bill and wondered if heating your pool is worth the shock to your wallet? The cost difference between heat pump and gas pool heater options might surprise you.

Gas pool heaters can drain anywhere from $300 to $500 per month from your budget. Heat pumps? They typically run at just $50 to $100 monthly. That's a difference that could pay for a family vacation.

But here's the thing—monthly bills only tell part of the story.

Gas heaters raise water tempearture faster than heat pumps (think hours, not minutes, for whole-pool changes). Speed depends on heater BTU and water volume in your pool. Heat pumps take their time but reward patience by extending your swimming season by 2-3 months depending on where you live. Natural gas versions cost less per hour than propane models, though both still run pricier than other heating options. Meanwhile, some guides estimate $0.63 an hour, to run a heat pump, but your cost depends on kWh price and unit size. Expect significantly lower running costs than gas in warm weather making them the clear winner for everyday swimmers during the winter months.

Let's figure out which option will actually save you money in 2025. 

Your local weather and swimming habits determine which heating system makes the most sense for your wallet. Pick wrong, and you'll either freeze during shoulder seasons or pay through the nose for heat you don't need.

Are Heat Pumps Best in Warm Climates (like Phoenix)?

Arizona pool owners have a clear winner here. Heat pumps work like magic when outdoor temperatures stay above 50°F—they steal warmth from the air around them rather than creating heat from scratch. The result? Efficiency ratings of 300%-700%. That means every dollar of electricity delivers 3-7 dollars worth of heat.

Even better, newer heat pumps come with automatic defrost features for those chillier nights. Some advanced models flip the script entirely during scorching summer months, actually cooling your pool water. Try getting that from a gas heater.

Are Gas/Propane Heaters Better in Cold Weather?

When temperatures drop below 45°F, heat pumps start struggling like a car with a dead battery. Gas heaters? They couldn't care less about the weather. Natural gas and propane units keep cranking out consistent heat even when winter decides to stick around.

Speed matters too. Gas heaters warm your pool in about an hour while heat pumps need several hours to do the same job. Modern gas pool heaters list 89%-95% thermal efficiency as per the department of energy.

Daily swimmers, heat pumps are your friend despite that higher upfront cost of $5,000-$8,000. Run one year-round at 85°F and you'll pocket about $400 annually in energy savings.

Weekend warriors and party hosts tell a different story. Gas heaters cost less upfront—around $1,500-$2,000 for gas line hookup—and heat water fast enough for spontaneous pool parties. Sure, that typical 400,000 BTU natural gas heater runs about $7 per hour, but occasional use keeps those costs manageable.

The math changes completely when you're heating every day.

Cost Breakdown - What Will Each Option Cost Me Over 5 Years?

The real question isn't just "which costs more upfront?" It's "which one will drain your wallet over the next five years?"

Here's what the numbers actually look like when you break them down.

How Much Do They Cost to Buy and Install?

Gas pool heaters give you a friendlier starting point—typically $1,500 to $6,000 for the equipment. Heat pumps demand more cash upfront, running $2,000 to $7,000.
Installation costs add another layer. Gas heaters need $500 to $1,500 for professional setup, while heat pumps usually cost $500 to $1,000 to install. The difference? Gas installations often require running new gas lines, which can push costs higher.

What Will I Pay Each Month to Run It?

This is where gas heaters start showing their true colors.

Gas heaters will hit you for $200 to $400 each month. Propane models? They can reach a painful $850 monthly. Heat pumps cruise along at just $50 to $150 per month.

Break it down by the hour and the gap gets even wider. Heat pumps cost about $0.63 per hour to run. Gas heaters? You're looking at $3 to $9 every hour

Here in Phoenix Valley, natural gas accessibility often makes your decision for you. Natural gas is usually cheaper per BTU than propane, but the gap depends on local prices. To compare, convert propane $/gal (≈91,500 BTU/gal) to $/therm and stack it against your gas $/therm.

A difference that can make or break your heating budget.

If you're stuck with propane tanks, those monthly bills start looking scary fast.

What Easy Tips Cut Heating Costs the Most?

Every degree you crank up that thermostat increases energy consumption by 10-30%. Here's how to keep more money in your pocket:

• Get a pool cover: This single step cuts heating costs by 50-90%
• Use timers: Run your equipment during off-peak hours when electricity rates drop
• Keep it maintained: Regular cleaning and maintenance keeps efficiency at peak levels

The biggest money-saver? Setting your thermostat just two degrees lower. You probably won't notice the difference, but your energy bill definitely will.

Cost matters, but performance decides whether you'll actually enjoy your heated pool.

Heating Time: 1 Hour vs Several Hours

Gas pool heaters don't mess around. They warm water at approximately 2°F per hour, while heat pumps take their sweet time at 1-1.5°F hourly. Need your pool 15-20 degrees warmer? Gas heaters finish the job overnight. Heat pumps? Plan on waiting multiple days.

This speed difference isn't just about convenience—it's about whether you can actually use your pool when you want to.

Temperature Consistency: On-Demand vs Gradual

Here's where things get interesting. Gas heaters excel at on-demand heating regardless of what Mother Nature throws at you. Perfect for those "let's heat the pool for this weekend's party" moments. Heat pumps work more like your home's HVAC system, maintaining consistent temperatures over time by automatically adjusting to keep your desired setting.

Think of gas heaters as a sprint runner and heat pumps as a marathon runner. Different strengths for different needs.

Energy Efficiency Ratings: BTU Output and COP

Heat pump efficiency gets measured by something called Coefficient of Performance (COP), typically ranging from 3.0-7.0. What does that mean in real terms? 300%-700% efficiency. Yes, you read that right—they can produce more heat than the electricity they consume.

Modern gas heaters offer 89%-95% efficiency ratings, which sounds impressive until you compare it to heat pumps' numbers.
BTU (British Thermal Unit) measures heating capacity. Most residential gas heaters pack 399,000 BTUs, absolutely crushing heat pumps' 50,000-140,000 BTU range. More power means faster heating, but also higher energy consumption.

Noise Levels and Space Requirements

Nobody wants a pool heater that sounds like a freight train. Heat pumps typically operate at 40-60 decibels—about as loud as your kitchen refrigerator. Newer inverter models whisper along at just 38.4 dB. Gas heaters produce slightly more noise plus minimal vibration when installed properly.

Both systems need adequate clearance for airflow and maintenance access, but neither should dominate your backyard landscape. 

Your pool's setup determines more than you might think about which heater will actually work best. Phoenix Valley pool owners deal with specific challenges that can make or break your heating investment.

Does an Above-Ground vs. In-Ground Pool Change My Choice?

Above-ground pools have a heating problem that catches most people off guard. They lose heat much faster through their exposed sides, requiring approximately twice the heating power of similarly sized in-ground pools. Think about it—your pool is basically sitting above ground with no insulation.
In-ground pools get a natural advantage from the earth's insulation, keeping heat locked in more efficiently. If you've got an above-ground pool, installing insulation beneath the liner can help minimize that heat escape. Without it, you're essentially heating the great outdoors.

If I Have a Spa + Pool, Which Heater Works Best?

Pool and spa combos create their own set of challenges. Some heat pumps come with built-in dual zone control systems that can maintain different temperatures simultaneously. Sounds perfect, right?
Here's the catch—gas heaters dominate when it comes to quickly raising spa temperatures to that perfect 95-105°F range, while heat pumps struggle with these higher temperatures. Hybrid heaters like Pentair's UltraTemp ETi combine both technologies, giving you fast heating and efficiency in one unit.

Will My Electrical Panel or Gas Line Limit My Options?

Your home's existing setup might make this decision for you. Heat pumps need a 240V outlet. Gas heaters require either natural gas lines or propane tanks.

Don't have gas lines? Installing new ones typically runs $1,500-$2,000. That expense might tip the scales toward heat pumps if you're starting from scratch with electrical access already in place.

If I Can Get Natural Gas, Is It Always Better Than Propane?

Natural gas costs approximately 85% less than propane—that's a massive difference for regular users. Propane means dealing with regular deliveries and finding storage space. Natural gas flows continuously through existing lines.

For those in remote Phoenix Valley locations without natural gas access, propane remains your best alternative. Just factor in those ongoing delivery costs when calculating your budget. 

Need the facts laid out side by side? Here's everything you need to compare these heating options at a glance.

Heat pumps win on monthly cost; gas wins on speed and cold-weather muscle. But the right choice for your pool depends on which factors matter most for your specific situation.

So which one actually saves you more money?

The honest answer is: it depends on your specific situation, and that's not just a cop-out response.

Heat pumps win the monthly cost battle hands down—$50-$100 versus $300-$500 for gas heaters. But gas heaters offer something heat pumps can't: instant gratification and reliable performance no matter what Mother Nature throws at you.

Here in Phoenix Valley, our warm climate makes heat pumps the smart money choice for most pool owners, especially if you're swimming regularly. That higher upfront investment pays for itself pretty quickly when you're not hemorrhaging money every month on energy bills.

But maybe you're that weekend warrior who just wants to heat the pool fast for a Saturday barbecue. Gas heaters make perfect sense for occasional use, even at $3-$9 per hour compared to the heat pump's $0.63.

Above-ground pool owners face a tougher choice because those exposed sides bleed heat like crazy. Sometimes the gas heater's speed trumps the heat pump's efficiency. Pool and spa owners? You might need to get creative with dual systems or hybrid options like Pentair's UltraTemp ETi.

And don't forget about what's already at your house. Natural gas costs about 85% less than propane, so if you've got gas lines, that changes the math entirely.

We've been helping Phoenix Valley pool owners figure out these decisions since 1966 at Shasta Pool Supply. Trust me, we've heard every possible scenario—from the snowbird who needs heat fast when they arrive in November to the year-round swimmer who wants to keep costs low. Our teams in Phoenix, Mesa, and Surprise have seen it all.

The right heating system should make your pool more enjoyable, not turn it into a monthly budget nightmare. Look at how you actually use your pool, consider what Arizona's climate means for your specific situation, and be honest about your budget—both now and long-term.

Heat pumps generally offer better value in our climate, but gas heaters solve specific problems that matter to some pool owners. The best choice is the one that fits your real-world needs, not what works for your neighbor.

Key Takeaways

Choosing between heat pumps and gas pool heaters in 2025 comes down to your climate, usage patterns, and long-term budget goals. Here are the essential insights to guide your decision:

• Heat pumps save 70-80% on monthly costs ($50-$100 vs $300-$500 for gas heaters) making them ideal for daily swimmers in warm climates above 50°F.
• Gas heaters heat pools 2x faster (2°F per hour vs 1-1.5°F) and work in all weather conditions, perfect for occasional use and cold climates.
• Climate determines efficiency: Heat pumps achieve 300-700% efficiency in warm weather, while gas heaters maintain consistent 89-95% efficiency regardless of temperature.
• Natural gas costs 85% less than propane, making gas line access a crucial factor in determining your most economical heating option.
• Installation infrastructure matters: Heat pumps need 240V electrical outlets while gas heaters require gas lines or propane tanks, potentially adding $1,500-$2,000 to setup costs.

For Phoenix Valley residents, heat pumps typically offer the best long-term value due to our warm climate and extended swimming seasons. However, weekend swimmers or those needing rapid heating may find gas heaters more practical despite higher operating costs.

Gas Pool Heaters https://www.energy.gov/energysaver/gas-pool-heaters

Heat Pump Swimming Pool Heaters https://www.energy.gov/energysaver/heat-pump-swimming-pool-heaters

UltraTemp ETi https://www.pentair.com/en-us/pool-spa/products/heaters-heat-pumps/ultratemp-high-performance-hybrid-heater.html