How to Heat a Room Cheaply | Stop Wasting Heat

The cheapest way to heat one room is to seal drafts, close the door, and run a thermostatically controlled space heater only while you’re in it.

Heating an entire home for one person sitting in one room is wasted money. The cheap approach is strategy first: block the cold from getting in, keep the warm air where you are, then use a small electric space heater as supplemental heat only for the room you occupy.

Portable electric space heaters convert nearly 100% of the electricity they draw into heat, but they only save you money when they let you turn down the central thermostat for the whole house. If you heat one room at 1,500 watts while the furnace also runs, you’re paying twice.

The Two-Step Cheap Heating Strategy

Cheap room heating starts with stopping heat loss, not adding more heat. Cold air leaking in makes any heater work harder and run longer than it should.

First, close the door to the room and block the bottom gap with a rolled towel or door draft stopper. Close the curtains or blinds to add a layer of insulation at the window. Seal obvious drafts around windows and doors with weatherstripping or caulk—this is the lowest-cost, highest-impact step.

Only then bring in heat. Run an electric space heater while you’re in the room and alert, turn it off when you leave, and rely on your main heating system for the rest of the house. This “zone heating” approach is exactly where space heaters make financial sense.

What Size Heater Do You Actually Need?

Bigger is not better—an oversized heater cycles on and off constantly and wastes electricity. Match the heater to the room, and prefer a model with a thermostat so it maintains a set temperature instead of blasting heat continuously.

That’s the size of a modest bedroom or a small living area.

A smaller 750-watt model handles a compact room or a home office, and many heaters offer both settings plus an eco or energy-save mode.

When you’re ready to buy, our tested roundup of affordable room heaters that actually work breaks down the top budget picks and which room each one handles best. If you’re choosing between a few models, Wirecutter’s space heater testing is a solid independent source for real-world heat output and safety performance.

Space Heater Safety Rules You Should Not Skip

The rules are simple but non-negotiable.

Keep the heater at least 3 feet away from curtains, furniture, bedding, and paper. Plug it directly into a wall outlet—never an extension cord or power strip, which can overheat. Place it on a flat, level, nonflammable surface, not on furniture or carpet. Never leave it running unattended or overnight, and unplug it when you leave the room.

Buy a model with three features: a tip-over switch that kills power if it falls, overheat protection, and a thermostat. Look for certification from a recognized testing lab like UL. Do not use a portable space heater in damp areas like a bathroom unless the label says it’s rated for that, and never use it to dry clothes, cook, or warm bedding.

FAQs

Is it cheaper to run a space heater or turn up the thermostat?

If you’re only using one room for hours at a time, a space heater is usually cheaper—it heats roughly 150 square feet directly instead of warming the entire house. The savings disappear if the central furnace still runs at full strength. Turn the thermostat down low, close the door, and heat only the room you occupy.

Are ceramic heaters more energy-efficient than other types?

Ceramic heaters warm up faster and distribute heat more evenly because the ceramic elements and fan push heat into the room quickly, letting the thermostat cycle off sooner. But when it comes to energy cost, nearly all electric space heaters convert about the same amount of electricity into heat—typically near 100%. The real difference is control, not conversion efficiency.

Can I use a space heater overnight safety?

You are unattended and less able to respond to a fire. If you need overnight warmth, add insulation to your bedding and use the central heat at a low setting instead, or use a heated blanket rated for overnight use.