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Quick Answer: What It Costs to Run a Patio Heater
A full-size propane patio heater (40,000 BTU) costs roughly $1.15 to $2.00 per hour to run, depending on how you buy your propane. A standard 1,500-watt electric infrared heater costs about $0.28 per hour at the current U.S. average electricity price of 18.83¢ per kWh. Electric infrared is far cheaper to run per hour, but propane throws off far more heat and covers a bigger, more open area.
In other words: if your only question is the hourly bill, electric wins. If you need to warm a wide, uncovered patio on a cold, breezy night, propane earns its higher cost. Below is the exact math, the current fuel prices we used, and the factors that push your real number up or down.
Last Updated: July 2026 | Will Montgomery has spent years researching and comparing outdoor patio heaters, tracking real propane and electricity costs across full heating seasons.
Patio Heater Running Cost Comparison (2026)
Here is what each common heater type costs to run, using current U.S. average fuel prices as of mid-2026. We show the cost per hour and the cost for a typical 4-hour evening.
| Heater type | Fuel use per hour | Fuel price (U.S. avg) | Cost per hour | Cost per 4-hr evening |
|---|---|---|---|---|
| Propane, 40,000 BTU (bulk/delivered propane) | ~0.44 gallons | $2.67 / gallon | ~$1.17 | ~$4.68 |
| Propane, 40,000 BTU (20-lb tank refills) | ~0.44 gallons | ~$4.50 / gallon | ~$1.98 | ~$7.92 |
| Electric infrared, 1,500 W | 1.5 kWh | 18.83¢ / kWh | ~$0.28 | ~$1.13 |
| Electric infrared, 3,000 W (commercial) | 3.0 kWh | 18.83¢ / kWh | ~$0.56 | ~$2.26 |
Sources: propane price from the U.S. Energy Information Administration residential survey ($2.67/gal, final 2025/26 heating-season figure); electricity price from the EIA U.S. residential average (18.83¢/kWh, April 2026). Propane energy content is 91,452 BTU per gallon.
How We Calculate the Cost to Run a Propane Patio Heater
The math is simpler than it looks. Propane contains about 91,452 BTU per gallon. Most freestanding propane patio heaters run at around 40,000 BTU per hour on high. So a heater burns roughly:
40,000 BTU ÷ 91,452 BTU per gallon = about 0.44 gallons of propane per hour.
Multiply that by your propane price and you have your hourly cost. At the current EIA residential average of $2.67 per gallon, that is about $1.17 per hour. But here is the catch most cost guides skip: very few patio-heater owners buy bulk propane. Most of us run a 20-lb tank, and refilling or exchanging those small tanks costs a lot more per gallon than bulk delivery. A refill at a hardware store or gas station often works out to $4 to $5 a gallon, which pushes the real cost closer to $2.00 per hour. Tank exchange cages (the swap-your-empty kind) are pricier still and are usually only filled to about 15 lbs, so your effective cost can top $2.50 an hour.
A useful shortcut we lean on: a full 20-lb tank holds about 4.6 gallons and lasts roughly 10 hours on high in a 40,000 BTU heater. So if a refill costs you $20, you are paying about $2 an hour. If you want to go deeper on tank life, we broke it down in our guide to how long a propane tank lasts on a patio heater.
How We Calculate the Cost to Run an Electric Patio Heater
Electric heaters are even easier to figure. A heater’s wattage tells you exactly how much power it draws. A standard plug-in electric infrared patio heater is 1,500 watts, which equals 1.5 kilowatt-hours (kWh) for every hour it runs on high.
1.5 kWh × $0.1883 per kWh = about $0.28 per hour.
That is it. At the current U.S. average residential electricity rate of 18.83¢ per kWh, a 1,500-watt infrared heater costs about 28 cents an hour, or a little over a dollar for a four-hour evening. Larger commercial-style infrared heaters draw 2,000 to 3,000 watts and cost proportionally more, but even a 3,000-watt unit runs at only about 56 cents an hour. Your own rate matters here, so check your utility bill: electricity ranges from roughly 11¢/kWh in the cheapest states to well over 30¢/kWh in the most expensive, which can double or halve the numbers above.
What Changes Your Real Running Cost
The table gives you a clean baseline, but a few things move your actual number:
- Heat setting. Running a propane heater on medium or low can cut fuel use by a third or more. Most people do not need full blast all night.
- Wind and open space. An exposed, breezy patio steals heat, so you run the heater harder and longer. A partially enclosed space holds warmth and lowers your cost.
- Heater size. A 46,000 BTU commercial propane heater burns noticeably more than a 40,000 BTU residential model. Bigger output means bigger fuel bills.
- Where you buy propane. As covered above, bulk delivery, station refills, and swap-cage exchanges can differ by 2× per gallon for the exact same fuel.
- Your local electricity rate. For electric heaters, this is the single biggest variable. Same heater, very different bill depending on your state and utility.
How to Lower Your Patio Heater Running Cost
A few practical moves we use to keep the cost down:
- Refill 20-lb tanks at a station instead of using exchange cages, or step up to bulk propane if you burn a lot of it.
- Turn the heater down once your space is warm. Radiant heat warms people, not air, so you rarely need maximum output the whole time.
- Add a windbreak, screen, or partial enclosure to trap heat and shrink your run time.
- For a covered patio, porch, or three-season room, choose electric infrared. It is cheaper per hour, has no open flame, and directs heat exactly where you want it.
- Match the heater to the space instead of oversizing. A too-big heater just burns more fuel to do the same job.
Propane vs. Electric: Which Is Actually Cheaper?
From experience: I run both a propane Mr. Heater and a three-setting electric infrared unit. The electric is clean and great over a covered patio or table area — but the moment the wind kicks up, it’s useless, because moving air overpowers radiant heat. I also couldn’t size the electric up: our pavilion was only wired with 14-gauge, which caps how big a unit you can run. So the real question isn’t just cost — it’s how much heat you actually need. Propane costs more per hour because it throws far more heat and holds up in open, breezy areas, while electric’s real edge is enclosed spaces: I’ll run it on a closed-in porch in winter, where you’d never want to burn propane.
Per hour, electric infrared is the clear winner on cost, often by 4 to 7 times. But cost per hour is only half the story. Propane produces two to three times the heat output of a typical plug-in electric heater, so it warms a larger, more open area and shrugs off cold and wind that would overwhelm a small electric unit. That is why the honest answer is “it depends on your space”:
- Covered patio, porch, balcony, or renter setup: electric infrared is cheaper to run, safer in enclosed areas, and needs no fuel storage.
- Open backyard patio or a big, breezy deck: propane costs more per hour but is the only one that will actually keep you warm.
We compare the two head-to-head in our full electric vs. propane patio heater breakdown. If you have already decided, see our current picks in best electric patio heaters and best propane patio heaters, or start with our overall best patio heaters guide.
Frequently Asked Questions
How much does it cost to run a propane patio heater per hour?
A standard 40,000 BTU propane patio heater burns about 0.44 gallons of propane per hour. At the current U.S. average bulk propane price of $2.67 a gallon, that is roughly $1.17 an hour. Because most people refill or exchange 20-lb tanks, which cost more per gallon, the real-world cost is usually closer to $2.00 an hour.
How much does it cost to run an electric patio heater?
A typical 1,500-watt electric infrared patio heater costs about $0.28 per hour at the current U.S. average electricity rate of 18.83¢ per kWh. That works out to a little over a dollar for a four-hour evening. Larger 3,000-watt commercial units cost about $0.56 an hour.
Is it cheaper to run a propane or electric patio heater?
Electric infrared is cheaper to run per hour, often by four to seven times, mainly because electricity is a lower-cost energy source for the heat it delivers. Propane costs more per hour but produces far more heat, so it is the better choice for large, open, or windy spaces where a small electric heater cannot keep up.
How long does a 20-lb propane tank last in a patio heater?
A full 20-lb propane tank holds about 4.6 gallons and lasts roughly 10 hours on the high setting in a 40,000 BTU heater. Running the heater on medium or low, or in a sheltered spot, can stretch that to 12 to 15 hours.
Does running a patio heater use a lot of electricity?
A 1,500-watt electric patio heater uses 1.5 kWh per hour, about the same as a space heater or a hair dryer. Over a four-hour evening that is 6 kWh, which costs a little over a dollar at average U.S. rates. It is a noticeable but modest addition to your bill, and much cheaper per hour than propane.
Why did my patio heater cost more to run than these estimates?
The two most common reasons are fuel source and local rates. If you buy propane through tank-exchange cages, you can pay double the bulk price per gallon. For electric heaters, living in a high-cost electricity state can push your rate above 30¢ per kWh, well over the national average used here.
Key Takeaways
- Propane patio heater: about $1.15–$2.00 per hour (40,000 BTU, depending on how you buy propane).
- Electric infrared heater: about $0.28 per hour (1,500 W at the U.S. average electricity rate).
- Electric is cheaper per hour; propane delivers more heat for big, open, windy spaces.
- Your two biggest cost variables are where you buy propane and your local electricity rate.
Prices in this guide reflect U.S. national averages as of mid-2026 and will shift with the seasons and your location. Written by Will Montgomery for Outdoor Space Accents.