How to use a space heater efficiently, and what it costs to run
Eight hours a day for 30 days is 360 kWh and $62.28 a month. The same heater costs $146.12 a month in Hawaii (40.59 cents) and $42.52 in North Dakota (11.81 cents). A heat pump that delivers the same warmth costs about $25.00.
The formula
Cost = watts ÷ 1,000 × hours × price per kWh. A 1,500-watt heater running one hour uses 1.5 kWh. At 17.30 cents per kWh that is 1.5 × 17.30 = 26.0 cents, or $0.260.
Watts are on the heater's label; the price per kWh is on your bill (total electric charges divided by kWh, or the energy rate on the rate schedule). For a bill with several charges, see how to read your electric bill. Most plug-in heaters switch between a low and a high setting, often near 750 and 1,500 watts, and a thermostat cycles the element on and off, so the label is the most the heater can draw, not what it averages.
What common heater settings cost at 17.30 cents per kWh
| Heater setting | Cost an hour | A month at 4 h a day | A month at 8 h a day | kWh a month at 8 h |
|---|---|---|---|---|
| 500 W | $0.087 | $10.38 | $20.76 | 120 |
| 750 W | $0.130 | $15.57 | $31.14 | 180 |
| 1,000 W | $0.173 | $20.76 | $41.52 | 240 |
| 1,500 W | $0.260 | $31.14 | $62.28 | 360 |
30 days a month. EIA 2025 U.S. average residential price: 17.30 cents per kWh. Energy charges only: your bill adds fixed charges and taxes.
Monthly cost by state
- $43 to $47
- $47 to $54
- $54 to $58
- $58 to $83
- $83 to $146
1,500 W, 8 hours a day, 30 days. Darker means a higher bill. Click a state for its price page.
All 51 areas in one table
| Hawaii | 40.59 | $0.609 | $146.12 | $58.66 | $87.47 |
|---|---|---|---|---|---|
| California | 32.54 | $0.488 | $117.14 | $47.02 | $70.12 |
| Massachusetts | 30.48 | $0.457 | $109.73 | $44.05 | $65.68 |
| Rhode Island | 29.46 | $0.442 | $106.06 | $42.57 | $63.48 |
| Connecticut | 29.38 | $0.441 | $105.77 | $42.46 | $63.31 |
| Maine | 27.78 | $0.417 | $100.01 | $40.14 | $59.86 |
| New York | 26.39 | $0.396 | $95.00 | $38.14 | $56.87 |
| Alaska | 26.09 | $0.391 | $93.92 | $37.70 | $56.22 |
| New Hampshire | 24.56 | $0.368 | $88.42 | $35.49 | $52.92 |
| Vermont | 22.92 | $0.344 | $82.51 | $33.12 | $49.39 |
| New Jersey | 22.63 | $0.339 | $81.47 | $32.70 | $48.77 |
| District of Columbia | 21.94 | $0.329 | $78.98 | $31.71 | $47.28 |
| Michigan | 20.01 | $0.300 | $72.04 | $28.92 | $43.12 |
| Maryland | 19.48 | $0.292 | $70.13 | $28.15 | $41.98 |
| Pennsylvania | 19.30 | $0.290 | $69.48 | $27.89 | $41.59 |
| Wisconsin | 18.16 | $0.272 | $65.38 | $26.24 | $39.13 |
| Illinois | 17.69 | $0.265 | $63.68 | $25.56 | $38.12 |
| Delaware | 17.13 | $0.257 | $61.67 | $24.75 | $36.91 |
| Ohio | 16.96 | $0.254 | $61.06 | $24.51 | $36.55 |
| Indiana | 16.23 | $0.243 | $58.43 | $23.45 | $34.97 |
| Alabama | 16.10 | $0.242 | $57.96 | $23.27 | $34.69 |
| Colorado | 15.85 | $0.238 | $57.06 | $22.90 | $34.16 |
| Minnesota | 15.82 | $0.237 | $56.95 | $22.86 | $34.09 |
| Texas | 15.47 | $0.232 | $55.69 | $22.36 | $33.34 |
| West Virginia | 15.41 | $0.231 | $55.48 | $22.27 | $33.21 |
| Oregon | 15.37 | $0.231 | $55.33 | $22.21 | $33.12 |
| Arizona | 15.32 | $0.230 | $55.15 | $22.14 | $33.01 |
| Virginia | 15.28 | $0.229 | $55.01 | $22.08 | $32.93 |
| Florida | 15.24 | $0.229 | $54.86 | $22.02 | $32.84 |
| New Mexico | 15.08 | $0.226 | $54.29 | $21.79 | $32.50 |
| South Carolina | 14.96 | $0.224 | $53.86 | $21.62 | $32.24 |
| Georgia | 14.73 | $0.221 | $53.03 | $21.29 | $31.74 |
| Kansas | 14.56 | $0.218 | $52.42 | $21.04 | $31.38 |
| Mississippi | 14.03 | $0.210 | $50.51 | $20.27 | $30.23 |
| North Carolina | 14.02 | $0.210 | $50.47 | $20.26 | $30.21 |
| Iowa | 13.72 | $0.206 | $49.39 | $19.83 | $29.57 |
| Missouri | 13.49 | $0.202 | $48.56 | $19.49 | $29.07 |
| South Dakota | 13.38 | $0.201 | $48.17 | $19.34 | $28.83 |
| Wyoming | 13.38 | $0.201 | $48.17 | $19.34 | $28.83 |
| Kentucky | 13.24 | $0.199 | $47.66 | $19.13 | $28.53 |
| Tennessee | 13.18 | $0.198 | $47.45 | $19.05 | $28.40 |
| Nevada | 13.15 | $0.197 | $47.34 | $19.00 | $28.34 |
| Oklahoma | 13.12 | $0.197 | $47.23 | $18.96 | $28.27 |
| Washington | 13.11 | $0.197 | $47.20 | $18.95 | $28.25 |
| Utah | 13.07 | $0.196 | $47.05 | $18.89 | $28.16 |
| Montana | 12.98 | $0.195 | $46.73 | $18.76 | $27.97 |
| Arkansas | 12.84 | $0.193 | $46.22 | $18.55 | $27.67 |
| Louisiana | 12.57 | $0.189 | $45.25 | $18.16 | $27.09 |
| Nebraska | 12.34 | $0.185 | $44.42 | $17.83 | $26.59 |
| Idaho | 11.82 | $0.177 | $42.55 | $17.08 | $25.47 |
| North Dakota | 11.81 | $0.177 | $42.52 | $17.07 | $25.45 |
Click a header to sort. EIA 2025 average residential price for each state, energy charge only. "Same heat, heat pump" divides the kWh by a seasonal COP of 2.49 (see below).
Your space heater cost
Uses the EIA 2025 state average price. Replace it with the rate on your own bill for a closer figure. The heater thermostat means real use is usually below the label wattage.
Space heater or heat pump: the same heat for less electricity
An electric resistance heater turns each kWh into one kWh of heat, whether it is a ceramic, oil-filled, infrared or baseboard unit. A heat pump moves heat instead of making it, so one kWh can deliver more than one kWh of heat. The ratio is the coefficient of performance (COP).
ENERGY STAR lists a heating efficiency, HSPF2, in Btu per watt-hour for every certified air-source heat pump. The median of the 285,054 listings is 8.5. One kWh is 3,412 Btu, so a seasonal COP is HSPF2 ÷ 3.412 = 2.49. The same list gives a median COP of 2.04 at 5°F (284,230 listings with that test), because output falls as the air gets colder.
The heat from a 1,500 W heater in 8 hours a day for 30 days is 360 kWh, or 1.23 million Btu. A heat pump at COP 2.49 makes that with 145 kWh, costing $25.00 at 17.30 cents instead of $62.28. At the 5°F COP of 2.04 it needs 176 kWh and costs $30.53.
Limits. A plug-in heater warms one room and a heat pump is installed equipment, so this compares electricity per unit of heat, not what you pay up front. Our heating cost pages assume a seasonal COP of 3.0 for a whole-home comparison with gas; the 2.49 here is the median listing, not a promise for your house. Our heat pump running cost page shows yearly cost by state.
Ways to spend less on a room heater
- Heat the room you are in and shut its door. The same watts warm a small closed room faster than an open floor plan.
- Pick a heater by its wattage and the room, not by its type. Every electric resistance heater makes the same heat per kWh, so a fan, ceramic or oil-filled unit changes how fast and how evenly the room warms, not the cost of a kWh of heat.
- Use the heater's own thermostat or timer instead of leaving it on high all night.
- Measure rather than guess: a plug-in power meter shows the kWh a heater actually used. At 17.30 cents per kWh, each kWh costs 0.17 dollars.
- Do not run it against a main thermostat that is also heating: lower the central thermostat while the room heater is on, or the two work against each other.
- Seal drafts around the room first; a heater loses part of what it makes to a leaky window.
Safety, in brief
This is general guidance, not a replacement for the manual or your fire department. We did not take distances or statistics from a source we could verify, so we give none: follow the manual.
- Plug an electric heater straight into a wall outlet. Avoid power strips and light extension cords, because a 1,500 W heater draws about 12.5 amps at 120 volts (watts ÷ volts).
- Keep bedding, curtains, clothes and paper well clear, and do not use it where it can get wet.
- Look for automatic shut-off if it tips over or overheats, and do not leave it running while you sleep or when you leave home.
- Fuel-burning heaters (kerosene, propane, gas) are a different product with a carbon monoxide risk; see our carbon monoxide guide.
- Check a model for recalls at the Consumer Product Safety Commission.
Related
Method and sources
Price: EIA, average residential price by state, 2025, from the state electricity profiles and sales data; it is revenue divided by kWh, so it includes some fixed charges and varies by utility. Heat pump efficiency: ENERGY STAR certified product data, retrieved October 2, 2026, median over listings, not weighted by sales. Scenario: 8 hours a day, 30 days a month. Calculation: methodology. Last updated October 5, 2026. The page changes when EIA publishes new prices or ENERGY STAR updates its list.
Questions
How much does it cost to run a space heater for an hour?
A 1,500 W heater costs $0.260 an hour at the U.S. average of 17.30 cents per kWh, from $0.177 in North Dakota to $0.609 in Hawaii.
How much does a space heater add to a monthly bill?
Running 1,500 W for 8 hours a day over 30 days uses 360 kWh and adds about $62.28 at the U.S. average price. At 4 hours a day it is about $31.14.
How do I work out the cost for my own heater?
Divide the watts on the label by 1,000, multiply by the hours you run it and by your price per kWh. For 750 W for 6 hours at 17.30 cents: 0.75 × 6 × 0.1730 = $0.78.
Is one type of space heater cheaper to run than another?
Not per unit of heat. Ceramic, oil-filled, infrared and baseboard electric heaters all turn each kWh into about one kWh of heat, so cost follows watts and hours. Type changes how quickly and evenly a room warms.
Is a heat pump cheaper than a space heater?
Per unit of heat, yes: at the median ENERGY STAR heating efficiency (HSPF2 8.5, COP 2.49) it uses about 60% less electricity, and at 5°F (COP 2.04) about 51% less. Installation cost is not included.
Why does the cost differ so much between states?
Because the price per kWh does: 40.59 cents in Hawaii against 11.81 in North Dakota, a gap of 3.4 times. The heater's watts are the same everywhere.
Will the heater really draw its full wattage?
Only while its element is on. A thermostat cuts power when the room reaches the set temperature, so the average draw is often lower than the label; a plug-in power meter shows the real number.