Home energy & efficiency

Space Heater Cost Calculator

See what running a portable space heater actually costs, and check whether the circuit it's on can handle it.

1. Heater & Usage

Heat Setting

Hours Used Per Day

Your Electricity Rate ($/kWh)

2. Running Cost

kWh × rate

MONTHLY COST

$—

SEASONAL COST (4 months)

$—

Circuit check: a 1500W heater draws 12.5A — close to the 80% continuous limit of a standard 15A circuit (12A). Never run it on a circuit already carrying other loads, and never on an extension cord rated below the heater's draw.

Space heater safety basics

Plug directly into a wall outlet — never into a power bar or extension cord unless it's rated for the heater's full draw.
Keep at least 3 ft of clearance from anything flammable (curtains, bedding, furniture).
Never leave running unattended or overnight in an occupied bedroom.
Look for a model with tip-over and overheat auto-shutoff.