All guides
Use the calculator for an instant estimate, or read on for a full breakdown of how this cost is calculated.
Quick Answer
$0.24/hr · ~$58/month (8 hrs/day)
Varies by equipment & usage
Space heater cost is straightforward: wattage ÷ 1,000 × hours used × $/kWh = cost. A 1,500W heater draws 1.5 kW. At $0.16/kWh, that's $0.24/hour.
Running it 8 hours a day for 30 days: 1.5 kW × 8 hrs × 30 days × $0.16 = $57.60/month. At 10 hours/day for a full cold month, that climbs to $72.
Most space heaters cycle on and off with a thermostat, so actual draw averages 50–70% of rated wattage in practice — but it's still significant. For heating an entire home, a central heat system is almost always more economical.
Estimate Your Cost
Heater wattage
Hours per day
4
hrs
Electricity rate
0.16
$/kWh
Est. monthly cost
$29.20
~2,190 kWh/year
Wattage — most portable heaters are 750W or 1,500W
Hours per day of use
Thermostat cycling — a thermostat-controlled heater draws less than rated wattage on average
Room size — smaller rooms reach set temperature faster, reducing run time
Home insulation — well-insulated rooms hold heat longer between cycles
Electricity rate in your area
Alternative heating cost — gas heat is typically cheaper per BTU than electric resistance
Pro Tip
The biggest savings usually come from upgrading the least efficient items first. Use Watt Wisdom to see exactly which loads are driving your bill before spending money on improvements.
Watt Wisdom calculates your full household energy profile — every appliance, your climate zone, and your usage habits — and tells you exactly what's driving your bill.
How Much Electricity Does a Heat Pump Use?
Heat pumps are 2–4x more efficient than electric resistance heating, making them one of th…
What Uses the Most Electricity in a Home?
In a typical U.S. home, HVAC (heating and cooling) accounts for roughly 45–50% of total el…
How Much Electricity Does a Water Heater Use?
Tankless electric heaters avoid standby losses but cost similarly per month for typical us…