How many kWh does a space heater use per month?

A 1500W heater running 8 hours/day for 30 days uses 360 kWh/month. A 1000W heater uses 240 kWh/month. A 500W personal heater uses 120 kWh/month at the same usage pattern.

Updated April 23, 2026

How Much Electricity Do Heaters Use?

Q: How much electricity does a space heater use?

A 1500-watt space heater uses 1.5 kWh of electricity per hour. Running 8 hours/day for 30 days uses 360 kWh/month. At $0.15/kWh average US rate, that costs $54/month.

kWh Usage — Every Wattage from 200W to 5000W

A 1500-watt space heater — the most common size — uses 1.5 kWh per hour, 12 kWh per day (8 hrs), and 360 kWh per month (8 hrs/day). At the US average rate of $0.15/kWh, that costs $54/month.

✓Formula: Wattage ÷ 1,000 = kWh per hour. Simple and exact.

Usage Table

kWh Usage by Wattage & Time Period

Monthly figures assume 8 hours/day for 30 days. Cost column uses US average rate of $0.15/kWh.

Wattage	Typical Use	kWh/Hour	kWh/Day (4 hrs)	kWh/Day (8 hrs)	kWh/Month	Cost/Month
200W	Personal desk heater	0.2 kWh	0.8 kWh	1.6 kWh	48 kWh	$7
400W	Mini ceramic heater	0.4 kWh	1.6 kWh	3.2 kWh	96 kWh	$14
500W	Small heater (low)	0.5 kWh	2 kWh	4 kWh	120 kWh	$18
750W	Small room supplemental	0.75 kWh	3 kWh	6 kWh	180 kWh	$27
1000W	Bedroom / small office	1 kWh	4 kWh	8 kWh	240 kWh	$36
1200W	Medium room	1.2 kWh	4.8 kWh	9.6 kWh	288 kWh	$43
1500W ★ MOST COMMON	Standard space heater	1.5 kWh	6 kWh	12 kWh	360 kWh	$54
2000W	Large room	2 kWh	8 kWh	16 kWh	480 kWh	$72
3000W	Workshop / basement	3 kWh	12 kWh	24 kWh	720 kWh	$108
5000W	Industrial / garage	5 kWh	20 kWh	40 kWh	1200 kWh	$180

Context

How Heaters Compare to Other Appliances

Appliance	kWh Per Hour	Context
1500W Space Heater	1.5 kWh	Most common portable heater
LED Light Bulb (10W)	0.01 kWh	1 hour = 0.01 kWh (150× less than heater)
Laptop (45W)	0.045 kWh	1 hour = 0.045 kWh (33× less than heater)
Refrigerator (150W)	0.15 kWh	1 hour = 0.15 kWh (10× less than heater)
Washing Machine (500W)	0.5 kWh	1 hour = 0.5 kWh (3× less than heater)
Electric Dryer (5,000W)	5 kWh	1 hour = 5 kWh (3.3× more than heater)
Central HVAC (3,500W avg)	3.5 kWh	1 hour = 3.5 kWh (whole-home heating)

Key insight: A 1500W space heater uses as much electricity as 150 LED bulbs running simultaneously. However, for zone heating, it still costs less than running central HVAC (3,500W+ for the whole home) just to heat one room.

FAQ

Heater Electricity Usage Questions

How much electricity does a space heater use?

A 1500-watt space heater uses 1.5 kWh per hour. Running 8 hours/day for 30 days uses 360 kWh/month. At $0.15/kWh average US rate, that costs $54/month.

How many kWh does a 1500-watt heater use per day?

A 1500-watt heater uses 6 kWh per 4 hours, 12 kWh per 8 hours, 18 kWh per 12 hours, and 36 kWh per 24 hours. Formula: wattage ÷ 1000 × hours = kWh.

Do space heaters use a lot of electricity?

Relative to other appliances, yes. A 1500W space heater uses as much electricity as 150 LED bulbs. However, for zone heating (one room instead of the whole house), space heaters are often more cost-effective than central heating which draws 3,500W+ for the whole home.

How many kWh does a 1000-watt heater use per month?

A 1000W heater uses 1 kWh per hour, 8 kWh per day (at 8 hrs), and 240 kWh per month. At $0.15/kWh, that costs $36/month.

How can I reduce how much electricity my heater uses?

Use a heater with ECO mode (reduces average wattage by 20–30%), set a programmable timer so it only runs when needed, lower the setting from 1500W to 1000W if the room is small enough, and ensure the room is well insulated to maintain warmth between cycles.

How Much Electricity Do Heaters Use?

kWh Usage by Wattage & Time Period

How Heaters Compare to Other Appliances

Heater Electricity Usage Questions

Related Tools & Guides