Space Heater Electricity Cost Calculator

How much does your heater add to your bill?

Quick Answer

A 1,500-watt space heater costs approximately $0.28 per hour to run at the U.S. average electricity rate of $0.18/kWh. That works out to $1.11 for a 4-hour session, $33.19 per month, or $199.15 over a typical 6-month winter season. Actual costs vary by state — from $0.19/hour in Idaho to $0.78/hour in Hawaii.

Electricity rates: U.S. EIA, May 2026

WattItCost is an independent appliance energy-cost calculator project.

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Summary

Formula

Cost = (Wattage ÷ 1,000) × Hours Used × Electricity Rate per kWh

Data used

Calculator results use user-entered wattage and usage hours, combined with residential electricity rates for the selected U.S. state or the rate entered from a utility bill.

Sources

EIA Electric Power Monthly Table 5.6.A residential

EIA data period: May 2026EIA source release date: July 23, 2026WattItCost site update date: July 30, 2026

Limits

These estimates do not reproduce a utility bill. Actual costs depend on your tariff, taxes, appliance cycling, efficiency, and how you use the appliance.

Electricity cost by state

Browse Space Heater Running Cost Calculator estimates for every U.S. state and the District of Columbia.

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How much does it cost to run a 1,500-watt space heater?

At the U.S. average electricity rate of $0.18/kWh, a 1,500-watt space heater costs $0.28 per hour to run. That’s $1.11 for 4 hours, $2.21 for 8 hours, $33.19 per month at 4 hours daily, or $66.38 per month at 8 hours daily.

Is it cheaper to use a space heater or central heating?

For heating one or two rooms, a space heater is usually cheaper — about $33.19/month at 4 hours daily, while gas furnace bills run $80–$120/month. Break-even is around 3 rooms.

Do all space heaters use the same amount of electricity?

All electric resistance heaters at the same wattage cost the same to run. A 1,500W ceramic and 1,500W oil-filled both cost $0.28/hour. The difference is heat delivery, not consumption.

What wattage space heater do I need for my room?

The standard is 10 watts per square foot. A 120 sq ft room needs 1,200W. A 225 sq ft room needs 2,250W.

How can I reduce my space heater electricity cost?

Use low mode (750W saves 50%), heat one room only, choose a thermostat model, use a 200W electric blanket at night ($0.04/hr vs $0.28/hr), and fix drafts.