Comparison · Cost
This is the one comparison on this site where the space heater loses on physics rather than on price — and it is not close.
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A heat pump moves existing heat rather than making it, so it delivers roughly two to four units of heat per unit of electricity — a coefficient of performance of 2 to 4. A space heater delivers exactly one. Per unit of heat, the heat pump costs a half to a quarter as much to run.
Everything else on this site treats electric heating as a 1:1 conversion, and for a resistive heater that is exact. A heat pump breaks the rule because it is not a heater in the same sense — it is a refrigerator run backwards, using electricity to move heat that already exists in the outdoor air into your house.
The measure of that is coefficient of performance: heat delivered divided by electricity consumed. A resistance heater has a COP of 1.0 by definition. A modern air-source heat pump typically runs between about 2 and 4 depending on the outdoor temperature — highest in mild conditions, falling as it gets colder.
| System | COP | Electricity for 5,118 BTU | Cost at 18.34¢/kWh |
|---|---|---|---|
| Space heater (resistance) | 1.0 | 1.500 kWh | 27.5¢ |
| Heat pump, cold conditions | 2.0 | 0.750 kWh | 13.8¢ |
| Heat pump, moderate conditions | 3.0 | 0.500 kWh | 9.2¢ |
| Heat pump, mild conditions | 4.0 | 0.375 kWh | 6.9¢ |
5,118 BTU/h is the output of one 1,500 W heater. Electricity at 18.34¢/kWh (EIA, June 2026). COP ranges are typical for modern air-source units and vary by model and outdoor temperature.
Read the last column. The same amount of heat costs 27.5 cents from a space heater and somewhere between 7 and 14 cents from a heat pump. Over a heating season that is not a rounding difference.
COP falls as the outdoor temperature falls, because there is less ambient heat available to move. In genuinely cold conditions a heat pump's advantage narrows, and many units include electric resistance elements as backup — at which point they are running at COP 1.0 and cost exactly what a space heater costs.
Cold-climate heat pumps have improved substantially and maintain useful output far below freezing, but the direction of the effect is not in dispute: the colder it is, the smaller the win. If you are comparing systems, get the manufacturer's published performance at your design temperature rather than the headline COP, which is measured in mild conditions.
Do not run a space heater instead of it. This is the one configuration where using a space heater is straightforwardly the more expensive option, even for a single room: the heat pump is already delivering two to four times the heat for the same electricity, and switching to a resistance heater to “save the heat pump running” costs you money.
The exception is a genuinely under-served room — an addition on a long duct run, a room the system was never sized for — where the heat pump cannot deliver the heat regardless of its efficiency. There, a space heater is closing a capacity gap rather than substituting for an efficiency one, and it is the correct tool.
Top pick · A whole living room
The rare heater whose published coverage claim survives the arithmetic: 1,500 W is a genuine 300 sq ft at 10 W/sq ft, and Dreo publishes that number rather than implying more.
| Published specification | |
|---|---|
| Rated power | 1,500 W at 120 V |
| Maker's coverage claim | 300 sq ft |
| Thermostat | 41–95°F digital, 1°F increments |
| Oscillation | 30° / 60° / 90° / 120° |
| Dimensions | 7.9" D x 7.9" W x 29.7" H, 8 lb |
| Safety | Tip-over cutoff, overheat cutoff, child lock, thermal cutoff |
| Heat type | Ceramic (PTC) |
| Maker’s coverage claim | 300 sq ft |
| Safety listing | ETL listed (stated by Dreo on the product page) |
Who it is for
A living room, bedroom or den at or under 300 sq ft with average insulation and an 8-foot ceiling, where you want to set a temperature and stop thinking about it.
What it is not for
A garage, an uninsulated basement, or anything over about 300 sq ft. It is not under-powered — 1,500 W is the plug-in ceiling — the room is simply too big for one outlet.
Yes, substantially. A heat pump delivers two to four units of heat per unit of electricity; a space heater delivers one. The same heat that costs 27.5 cents from a space heater costs roughly 7 to 14 cents from a heat pump.
No. The heat pump is already producing more heat per kilowatt-hour, so substituting a resistance heater costs more. The exception is a room the heat pump genuinely cannot reach, where a space heater is closing a capacity gap.
Coefficient of performance — heat delivered divided by electricity consumed. Resistance heating is 1.0 by definition. Modern air-source heat pumps typically run 2 to 4, falling as the outdoor temperature drops.
They lose efficiency as the outdoor temperature falls, and many units switch to electric resistance backup in extreme cold — where they cost the same as a space heater. Cold-climate models maintain useful output well below freezing.
Per-BTU arithmetic for gas, oil and electric — and the one condition that decides the answer.
A correction, not a product pick: equal wattage means equal cost, and here is what actually varies.
Same physics, same cost per kWh — so the comparison is zoning, control and wattage.
All electric heaters are 100% efficient. These are picked on the three things that actually cut the bill.
The monthly figure at 4, 8, 12 and 24 hours a day — including the 24/7 case, computed.
10,000 W of demand, 1,500 W of supply. Why “heats 1,000 sq ft” listings are not describing heat.