Is a Space Heater Cheaper Than Central Heat?

On this page (8 sections)

1. When is a space heater cheaper than central heat?
2. How do you compare the two heating costs?
3. Which heater features help with one-room heating?
4. How can you measure electricity use without changing the heater connection?
5. Should you seal drafts before adding more heat?
6. Is a plug-in thermostat worth adding?
7. How should you set up and use a heater to avoid wasted energy?
8. How should you decide between a space heater and central heat?

A space heater can be cheaper than central heat when you warm one occupied room and lower central heating elsewhere. It saves money only if the central heating you avoid costs more than the electricity you add.

That makes a home office used for a few hours a better candidate than several rooms occupied all day. Start with your heating system and daily routine before buying another appliance.

When is a space heater cheaper than central heat?

A space heater is most likely to save money during short periods of single-room use with central heat turned down. Running it alongside an unchanged central thermostat usually adds to your bill.

A person working in one room can keep that space comfortable without maintaining the same temperature throughout the home. The case is weaker when family members need warmth in different rooms or doors must stay open.

Drafts also matter because escaping warmth keeps the heater running longer. If a room never reaches a comfortable temperature, address heat loss before adding more portable heaters.

When is central heat cheaper than a space heater?

Central heat can be cheaper when several rooms need warmth or an efficient heat pump serves the occupied space. A small electric appliance does not automatically deliver cheaper heat.

Electric resistance heaters turn electricity into heat at the point of use. A heat pump moves heat, so it can deliver more heat per unit of electricity, although performance changes with outdoor conditions and equipment.

For gas, oil, or propane systems, compare local fuel costs and system efficiency with electricity costs. A fuel unit and a kilowatt-hour are different measures, so comparing their unit charges alone tells you little.

How do you compare the two heating costs?

Compare total heating expense over the same period, including both the portable heater and the central system’s remaining use. The useful question is how much central heating your new routine actually replaces.

For the space heater, use:

Power in kilowatts × hours heating × electricity rate per kilowatt-hour = estimated electricity cost.

A 1500-watt heater draws 1.5 kilowatts while heating at full power. At that level for 4 hours, it uses 6 kilowatt-hours; multiply that total by your electricity rate.

Thermostat cycling can reduce actual consumption below a continuous full-power estimate. A lower setting saves energy while running, but it may need to run longer to maintain the same room temperature.

Our guide to how much it costs to run a space heater explains the calculation. For household demand, see whether space heaters use a lot of electricity.

How can you make a fair household comparison?

Record a baseline, then change one part of your heating routine. Compare several periods with similar outdoor temperatures, occupied hours, and indoor comfort rather than judging from one unusually mild day.

Record the central thermostat setting, heater use, and electricity consumption. If central heat uses another fuel, include that consumption too, since a lower gas bill can hide a larger electric bill.

Use the usage portion of your bills when comparing savings. Fixed service charges generally remain even when you use less energy.

Which heater features help with one-room heating?

A thermostat and suitable heat output matter more than an energy-saving label. Choose a heater that can maintain comfort in your room without buying several units to cover a larger space.

The DREO 1500W Thermostat Heater has 1000W and 1500W heat settings, with ECO mode that adjusts operation based on room temperature. It suits someone who wants built-in temperature control for an occupied office or sitting room.

DREO gives this indoor ceramic model a coverage figure of 270 sq ft. Use that as a starting point because insulation, ceiling height, and open doorways affect the heat a room needs.

Its 70° oscillation helps spread airflow across a seating area. Skip it as a whole-home replacement or if your room cannot provide the clearances required by its manual.

The built-in thermostat also removes the need for a separate plug-in controller. For alternatives by heater type, see our space heaters for home guide.

For electrical demand, read how many watts a space heater uses. Our energy-efficient space heater guide helps compare controls and suitable uses.

How can you measure electricity use without changing the heater connection?

Use whole-home energy readings for a heater that requires a direct wall connection. Plug-in monitors suit only appliances whose instructions permit that connection and whose electrical requirements match the monitor.

The Kill A Watt Meter records kilowatt-hours and uses your electricity rate to forecast costs. It suits someone comparing compatible plug-in appliances or investigating other electricity use that may obscure heating savings.

Skip this meter for the DREO heater, which must connect directly to a wall outlet. For other heaters, confirm compatibility in both manuals before using a monitor.

Forecasts reflect the period measured, so a short reading during warm-up may exaggerate typical use. Whole-home readings also need context because cooking, laundry, and other appliances can change consumption during the comparison.

Should you seal drafts before adding more heat?

Seal avoidable drafts first when cold air enters around windows. Reducing heat loss helps whichever heating system you use and may make an existing room heater sufficient.

Check window edges for incoming air before assuming you need a larger heater. Keep curtains and furniture clear of heaters and central vents.

The Duck Window Insulation Kit creates an indoor film barrier against window drafts. It suits households with several drafty windows that can stay sealed through the cold season.

The kit includes 2 rolls of 62 x 210 in film and tape, enough for up to 10 standard 3 x 5 ft windows. Installation needs scissors and a hair dryer on clean, dry painted or finished wood, aluminum, or vinyl surfaces.

Clean and dry the attachment area before applying the tape, then follow the directions for shrinking the film. Check the edges during the season for loose sections that let drafts return.

Skip film on windows you need to open regularly, and never obstruct a required emergency exit. Film is also no substitute for repairing damaged frames or addressing water leaks.

Is a plug-in thermostat worth adding?

A separate thermostat helps only when the appliance permits external control. It can sense temperature near your seat, but it cannot make every heater safe or suitable for that connection.

The DIGITEN Plug-In Thermostat has a temperature sensor in its remote and stops power to a connected appliance at the target temperature. It suits someone with a compatible appliance who wants temperature control elsewhere in the same room.

Its maximum load is 15A and 1800W, and the remote requires 2 AAA batteries that are not included. Both manuals must permit the connection; the electrical limit alone is not enough.

Keep the remote and receiver in the same space, with the sensor away from direct heater airflow, sunlight, and cold drafts. Those locations can make the sensed temperature differ from the area you occupy.

Skip this controller for the DREO because it requires a direct wall connection. Also confirm how any compatible appliance behaves when power returns, since external control depends on that behavior.

How should you set up and use a heater to avoid wasted energy?

Heat the occupied area with a modest thermostat setting and a clear airflow path. Keep central heat high enough for the rest of the home’s occupants and plumbing.

Place the heater on a stable surface and follow its required clearances from furniture, bedding, and curtains. Plug the DREO directly into a wall outlet, and stop using any heater with a damaged cord or loose plug connection.

A closed door can retain warmth, but follow your central system’s airflow requirements. Don't block vents or close multiple registers in an attempt to force savings.

Turn the heater off before sleeping or leaving it unattended. Timers, tip-over protection, and overheat protection do not replace that routine.

Unplug the heater and let it cool before cleaning its intake and outlet as directed. Keep clothing off the unit and avoid placing furniture where it restricts airflow.

The most common cost mistake is leaving central heat unchanged while running a portable heater for hours. Another is treating several portable heaters as a cheap whole-home system without adding up their combined electricity use.

Read our space heater safety guidance before setting up a unit. For connection questions, see whether a space heater can use an extension cord.

How should you decide between a space heater and central heat?

Choose a space heater for limited use in one room when lowering central heat produces greater savings than the added electricity costs. Choose central heat when several rooms need warmth or your system heats the occupied area more cheaply.

For drafty windows, start with sealing rather than extra heat. Buy a meter or external thermostat only when you have a compatible appliance and a clear use for it.

Whether a space heater is cheaper than central heat depends on the heating it replaces. Use our space-heater running costs guide to plan the comparison, then keep the approach that maintains comfort at the lower total cost.

Frequently asked questions

Is it cheaper to run a space heater or central heat?

A space heater can cost less for one occupied room when you lower central heating elsewhere. Central heat often makes more sense for several rooms, especially with an efficient heat pump, so compare the added electricity with the central heating expense you avoid over the same period.

How much does it cost to run a 1500-watt space heater?

A 1500-watt heater uses 1.5 kilowatt-hours for each hour its heating element runs at full power. Multiply that amount by your electricity rate for an hourly estimate, then multiply by heating hours; time spent switched off by a thermostat does not count as full-power heating.

Can a space heater lower my heating bill?

A space heater can lower your total heating bill if its electricity costs less than the central heating it replaces. Compare both electricity and fuel bills when your central system uses gas or another fuel, and account for weather changes before deciding that a smaller fuel bill means savings.

Should I turn off central heat when using a space heater?

Usually, lower central heat rather than shutting it off, because other rooms may still need warmth for people, pets, and plumbing. Follow your heating system’s guidance on setbacks and airflow, and turn a portable heater off before sleeping or leaving it unattended, even when it has automatic shutoff features.