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Updated July 2026 rate dataHeating & CoolingSourced from U.S. EIA
Space heaters cost what their thermostat lets them: once the room reaches temperature, a thermostat or eco mode cycles the element off, and a drafty room keeps that cycle running longer. Set your heater's wattage and your state below for the exact figure.
EIA residential average, July 2026. Your utility's exact rate is on your bill.
Real-time math: 1,500 W × your state's rate, accumulating live. Thermostatically controlled units cycle on and off, so average use is usually below the flat-out figure.
Run like this for a year and it adds about $601 to your electricity bill.
Uses the U.S. average residential rate of 18.31¢/kWh (EIA, July 2026). Most space heaters are 1,500 W on high and 750 W on low; the wattage you set is the element's draw while it is on.
Energy: 9 kWh per day · 3,285 kWh per year, at 18.31¢/kWh (U.S. average).
Wattage is the number that decides everything else. The table below runs the actual figures through this page's calculator at the U.S. average rate of 18.31¢ /kWh, so you can see the running cost jump as the load climbs. Change any value above and the whole page recalculates.
| Watts | Power draw | Per hour | Per month (6 h/day) |
|---|---|---|---|
| 200 W | 200 W draws 0.20 kW | $0.037 | $6.68 |
| 1,135 W | 1,135 W draws 1.14 kW | $0.21 | $37.93 |
| 2,065 W | 2,065 W draws 2.06 kW | $0.38 | $69.01 |
| 3,000 W | 3,000 W draws 3.00 kW | $0.55 | $100 |
Basis: July 2026 U.S. average residential rate of 18.31¢ /kWh (EIA Electric Power Monthly, Table 5.6.A). Your state's rate is applied as soon as you pick it above.
Most heaters don't run the element continuously. Once the room reaches temperature, a thermostat or eco mode cycles the element off and back on. A heater that runs its element 60% of the hour costs 60% of the nameplate figure — that is why a drafty basement costs more than an insulated bedroom.
Portable heaters almost always draw 1,500 W on high and about 750 W on low, regardless of price or brand. 'Infrared', 'ceramic', and 'oil-filled' describe how heat is delivered, not how much energy is used — a 1,500 W oil-filled radiator and a 1,500 W ceramic fan heater cost exactly the same per hour.
The same heater costs about $0.192 per hour in Nevada and $0.720 per hour in Hawaii. Because space heaters can easily add 200+ hours over a winter, the state rate is the single biggest long-run difference. Pick your state below for exact numbers.
A heater fights the room's leaks: single-pane windows, uninsulated walls, doors left ajar. Sealing drafts and closing doors to unused rooms lowers the duty cycle — the hours the element actually runs — which is where the real savings live.
Biggest savings first.
At the U.S. average rate of 18.31¢/kWh, a 1,500 W heater running flat out for 24 hours uses 36 kWh and costs about $6.59. In cheap-electricity states it is closer to $4.60; in Hawaii about $17.28. Most real usage is shorter with thermostat breaks, so treat 24-hour flat-out as the ceiling.
Yes — per hour they are among the heaviest plug-in loads in a home: 1,500 W is like running a large window AC or about 15 laptops at once. The saving grace is that they run for part of the day in one room, and the thermostat cycles them off periodically.
Per unit of heat, electric resistance heat costs the same whether it is in a furnace or a portable heater. A space heater is cheaper only when it lets you heat one occupied room instead of the whole house — that is the zone-heating strategy. If you keep the whole house just as warm as before, the space heater is pure added cost.
Running 1,500 W for 6 hours a day costs about $50/month at the U.S. average rate (18.31¢/kWh, 30.4-day month). At 2 hours a day it is closer to $17/month. Use the calculator above with your own hours and state rate for a precise figure.
Electricity rates are set state by state — the U.S. average is about 18¢/kWh, but the cheapest states pay around 13¢ and the most expensive pay over 50¢. The same heater on the same schedule can cost 2–4× more depending on where you live.
Rate basis: EIA residential average, July 2026 (retrieved from Electric Power Monthly Table 5.6.A). Estimates are for planning, not billing.
