How much does it cost to run a space heater for 8 hours?

About $2.08 for a 1,500-watt heater on high at the 2025 U.S. average rate of 17.3¢ per kWh (1.5 kWh × 8 hours × 17.3¢). On the 750-watt low setting it's about $1.04. In a high-rate state like California it's closer to $3.90.

Does a space heater on low save money?

Per hour, yes: a 750-watt low setting uses half the electricity of 1,500-watt high. But a heater on low may need to run longer to warm the room, so the saving over a whole evening is usually less than half.

How do I know how many watts my heater uses?

It's printed on the rating label, usually on the back or bottom, and in the manual. Most plug-in heaters top out at 1,500 watts on high. That draws 12.5 amps at 120 volts, most of what a standard 15-amp household circuit carries, which is why a heater and a hair dryer on the same circuit can trip the breaker. Low settings are often 750 or 900 watts.

Is it cheaper to use a space heater than central heat?

It can be, if you heat only the room you're in and turn the central thermostat down for the rest of the house. Electric resistance heat costs more per unit of heat than a heat pump and usually more than gas, so heating the whole house with space heaters rarely saves money.

Why did my electric bill jump when I started using a space heater?

Because it adds up fast: 1,500 watts for 10 hours a day is 450 kWh a month, about $78 at the U.S. average rate. Use the calculator with your own hours and your bill's rate to see your share.

Space Heater Cost Calculator: About 26¢ an Hour

About 26¢ an hour for a standard 1,500-watt heater at the average U.S. electricity rate. Pick your state for your own number, or switch to another appliance.

How the calculator works

Electricity is billed by the kilowatt-hour (kWh): 1,000 watts running for one hour. So the cost of any plug-in appliance is watts × hours ÷ 1,000 × your rate. A 1,500-watt heater running for an hour uses 1.5 kWh; at 17.3¢ per kWh that's 26¢.

The calculator starts with your state's average residential rate for 2025 (preliminary) from the U.S. Energy Information Administration. Your bill can be higher or lower: delivery charges, tiers and time-of-use plans all change it. For your real all-in rate, divide your last bill's total by the kWh it lists.

The share of the time it runs at full power matters more than people expect. A heater with a thermostat switches its element off once the room reaches the set temperature and back on as it cools. In a small, well-sealed room it may heat only part of each hour; in a drafty one it can run nonstop. If you don't know, leave it at 100% for the most it could cost.

What a 1,500-watt space heater costs to run, by state

On high, at each state's average residential rate (2025, preliminary). "A month" is 8 hours a day for 30 days.

State	Rate	Per hour	A month
U.S. average	17.3¢/kWh	26¢	$62
Alabama	16.1¢/kWh	24¢	$58
Alaska	26.1¢/kWh	39¢	$94
Arizona	15.3¢/kWh	23¢	$55
Arkansas	12.8¢/kWh	19¢	$46
California	32.5¢/kWh	49¢	$117
Colorado	15.9¢/kWh	24¢	$57
Connecticut	29.4¢/kWh	44¢	$106
Delaware	17.1¢/kWh	26¢	$62
District of Columbia	21.9¢/kWh	33¢	$79
Florida	15.2¢/kWh	23¢	$55
Georgia	14.7¢/kWh	22¢	$53
Hawaii	40.6¢/kWh	61¢	$146
Idaho	11.8¢/kWh	18¢	$43
Illinois	17.7¢/kWh	27¢	$64
Indiana	16.2¢/kWh	24¢	$58
Iowa	13.7¢/kWh	21¢	$49
Kansas	14.6¢/kWh	22¢	$52
Kentucky	13.2¢/kWh	20¢	$48
Louisiana	12.6¢/kWh	19¢	$45
Maine	27.8¢/kWh	42¢	$100
Maryland	19.5¢/kWh	29¢	$70
Massachusetts	30.5¢/kWh	46¢	$110
Michigan	20.0¢/kWh	30¢	$72
Minnesota	15.8¢/kWh	24¢	$57
Mississippi	14.0¢/kWh	21¢	$51
Missouri	13.5¢/kWh	20¢	$49
Montana	13.0¢/kWh	19¢	$47
Nebraska	12.3¢/kWh	19¢	$44
Nevada	13.2¢/kWh	20¢	$47
New Hampshire	24.6¢/kWh	37¢	$88
New Jersey	22.6¢/kWh	34¢	$81
New Mexico	15.1¢/kWh	23¢	$54
New York	26.4¢/kWh	40¢	$95
North Carolina	14.0¢/kWh	21¢	$50
North Dakota	11.8¢/kWh	18¢	$43
Ohio	17.0¢/kWh	25¢	$61
Oklahoma	13.1¢/kWh	20¢	$47
Oregon	15.4¢/kWh	23¢	$55
Pennsylvania	19.3¢/kWh	29¢	$69
Rhode Island	29.5¢/kWh	44¢	$106
South Carolina	15.0¢/kWh	22¢	$54
South Dakota	13.4¢/kWh	20¢	$48
Tennessee	13.2¢/kWh	20¢	$47
Texas	15.5¢/kWh	23¢	$56
Utah	13.1¢/kWh	20¢	$47
Vermont	22.9¢/kWh	34¢	$83
Virginia	15.3¢/kWh	23¢	$55
Washington	13.1¢/kWh	20¢	$47
West Virginia	15.4¢/kWh	23¢	$55
Wisconsin	18.2¢/kWh	27¢	$65
Wyoming	13.4¢/kWh	20¢	$48

Ways to spend less on it

Heat the room, not the house. A space heater saves money only when you turn the central thermostat down at the same time. Running both just adds the heater to the bill.
Close the door and stop the drafts. A heater in a drafty room runs nonstop. Draft stoppers and window film cut the hours it has to work.
Use the thermostat and the timer. Set it to the lowest comfortable temperature and let it switch off, instead of leaving it on high.
Warm yourself, not the air. An electric blanket draws about 60 to 100 watts, a small fraction of a heater's 1,500.

Use it safely. Plug a space heater straight into a wall outlet, never an extension cord or power strip. Keep it at least 3 feet from anything that can burn: bedding, curtains, furniture, paper. Choose one with tip-over and overheat shut-off, and turn it off when you leave the room or go to sleep. Space heaters and heating stoves cause about 30% of U.S. home heating fires but 73% of the deaths from them (NFPA, 2020–2024 averages).

How much does a space heater cost to run?

How the calculator works

What a 1,500-watt space heater costs to run, by state

Ways to spend less on it

Sources

Frequently asked

Read more about it

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