How much does a space heater cost to run?

A 1,500-watt unit running 5 hours a day costs about $42.37 a month at 18.83¢ per kWh. Change the inputs for your equipment and local rate.

Updated July 16, 2026EIA residential rate data

Calculate your cost

Start with a representative input, then edit all three numbers.

18.83¢/kWh U.S. average
W
hr
¢/kWh
$42.37/ month
$1.41/ day
$515.47/ year

This setup uses about 225 kWh in a 30-day month.

Runtime comparison
ScheduleHours/dayCost/month
Half runtime2.5$21.18
Starting point5$42.37
Longer runtime7.5$63.55

Same 1,500-watt input and 18.83¢/kWh rate; only runtime changes.

The quick formula

1.5 kW × 5 hours × $0.1883 = $1.41 per day

Convert watts to kilowatts, multiply by the active hours used each day, then multiply by the electricity price in dollars per kWh. Multiply the daily result by 30 for the monthly estimate shown above.

How to read this estimate

Most plug-in space heaters draw close to the maximum load of a standard household outlet when heating at full power. Even a small heater can therefore add a noticeable amount to a monthly bill when it runs for several hours every day.

The starting values keep this page useful before you have a label or meter reading. They do not describe every model, climate, operating mode, or household.

What changes the cost?

  1. 01

    High, low, or thermostat-controlled heat setting

  2. 02

    Room insulation, drafts, and outdoor temperature

  3. 03

    Daily runtime and whether the heater cycles off

Ways to spend less

  • Heat the occupied room and keep doors closed.
  • Use the thermostat instead of leaving the heater on continuously.
  • Stop drafts around doors and windows before increasing the setting.

Rate source U.S. Energy Information Administration, Electricity Retail Sales

EIA calculates average retail revenue per kilowatt-hour from reported residential sales and revenue. It is a statewide monthly average, not a quoted utility tariff, and an individual bill may also include fixed fees, tiers, taxes, riders, or time-of-use pricing.

Source period 2026-04 · retrieved July 16, 2026.