How Much Does It Cost to Run a Space Heater Per Hour?

Calculate the cost of running a 1,500-watt space heater per hour, day and month. Compare heat settings, thermostat cycling and energy-saving options.

APPLIANCE POWER USE

WattBasis Editorial Team

9/6/20266 min read

Quick Answer

A 1,500-watt space heater costs approximately $0.24 per effective heating hour at an electricity rate of $0.16 per kWh. If its heating element operates for six effective hours per day, it would cost about $1.44 per day or $43.20 over a 30-day month. Thermostat cycling, heat settings, insulation, room size and your local electricity rate determine the actual cost.

Portable electric space heater warming a cozy room in winter

White electric space heater in a bright living room for an electricity cost guide

How to Read Your Calculator Result

A space heater’s advertised wattage shows how much electrical power it draws while the heating element is active. It does not necessarily mean the heater consumes that amount continuously.

Use this formula:

Cost = (watts ÷ 1,000) × effective heating hours × electricity rate

“Effective heating hours” means the total time the heating element is actually drawing power. A heater may remain switched on for six hours while its thermostat cycles the heating element on and off.

What a 1,500-Watt Space Heater Really Costs

At an illustrative electricity rate of $0.16 per kWh, a 1,500-watt heater costs approximately:

$0.24 per effective heating hour
$0.72 for three effective hours
$1.44 for six effective hours
$43.20 per month when used for six effective hours per day over 30 days

The monthly calculation is:

1,500 watts ÷ 1,000 = 1.5 kilowatts

1.5 kW × 6 hours × 30 days = 270 kWh

270 kWh × $0.16 = $43.20 per month

These are calculated examples rather than guaranteed averages. Enter the electricity rate shown on your own utility bill for a more accurate estimate.

750 Watts vs. 1,500 Watts

If both settings operate for the same amount of time, a 750-watt setting uses half as much electricity as a 1,500-watt setting.

At $0.16 per kWh:

750 watts: $0.12 per effective hour
1,000 watts: $0.16 per effective hour
1,500 watts: $0.24 per effective hour

However, the lower setting may need to run longer to warm the room. The cheapest option is normally the lowest setting that keeps the occupied area comfortable without operating continuously.

What Makes a Space Heater Expensive to Run?

The heater’s wattage determines its cost while actively heating, but the room determines how long it needs to operate.

The biggest factors are:

Room size and ceiling height
Outdoor temperature
Insulation quality
Drafts around windows and doors
Thermostat setting
Open doors to adjoining rooms
Low, medium or high heat setting
Local electricity price
Number of hours used each day

A heater in a small, closed and insulated room may cycle off regularly. The same heater in a large or drafty space may remain at full power for much longer.

Which Heater Type Costs Less?

A heater’s type does not automatically determine its operating cost. Wattage and effective operating time matter more.

Ceramic fan heaters warm the surrounding air quickly and can be useful for short periods, although the fan produces some noise.

Oil-filled radiators warm more slowly and release stored heat gradually. They are quiet and may provide steadier comfort, but the oil does not create free energy.

Infrared heaters direct warmth toward people and nearby objects. They can feel effective when heating one occupied area rather than an entire room.

Convection and panel heaters warm the air around them. Their performance depends heavily on room size, insulation and airflow.

Two electric heaters drawing 1,500 watts for the same amount of time will use the same calculated electricity, even if they deliver the heat differently.

Can a Space Heater Lower Your Heating Bill?

Possibly—but only in the right situation.

A portable heater may reduce total heating costs when it warms one occupied room while the rest of the home remains at a lower temperature. This can be practical for a home office or bedroom used for a limited period.

It may not save money if you continue heating the entire home normally or operate several portable heaters simultaneously. Three 1,500-watt heaters running at full power would draw approximately 4,500 watts.

The result depends on your main heating system, energy prices, insulation and the amount of space being heated.

Seven Ways to Reduce Space Heater Electricity Use

1. Heat only the occupied room

Turn the heater off when nobody is using the room. Heating empty areas adds consumption without improving comfort.

2. Close the door

Keeping warm air inside a smaller area can help the thermostat reach its target sooner.

3. Seal noticeable drafts

Check windows and exterior doors for cold air. Drafts can make the heating element operate more frequently.

4. Use the lowest comfortable setting

If 750 or 1,000 watts provides enough warmth, there is no reason to keep the heater at 1,500 watts.

5. Use the thermostat and timer

A thermostat prevents unnecessary continuous heating, while a timer reduces the chance of forgetting that the heater is running.

6. Avoid large open spaces

Portable heaters are generally better suited to smaller occupied rooms than open-plan areas.

7. Measure real consumption

A compatible electricity monitor can show how much power the heater actually uses. Measure several representative days because one mild day may not reflect extremely cold weather.

Essential Space Heater Safety

Saving electricity is never more important than using the heater safely.

The U.S. Consumer Product Safety Commission recommends keeping portable heaters at least three feet away from curtains, bedding, furniture and other combustible materials.

Always:

Place the heater on a stable, level surface
Plug it directly into a wall outlet
Avoid extension cords and power strips
Keep the heater away from water
Never cover it or block its airflow
Keep children and pets away from hot surfaces
Turn it off before leaving the room
Do not leave it operating while sleeping
Stop using it if the cord, plug or outlet becomes unusually hot
Follow the manufacturer’s instructions and recall notices

Space Heater Cost FAQs

How much does a 1,500-watt heater cost per hour?

At $0.16 per kWh, it costs approximately $0.24 per effective heating hour. At $0.20 per kWh, it costs approximately $0.30 per hour.

How much does a space heater cost to run all night?

A 1,500-watt heater drawing full power for eight hours would consume 12 kWh. That equals approximately $1.92 at $0.16 per kWh or $2.40 at $0.20 per kWh.

This is only a mathematical example. Portable space heaters should not be left operating while you sleep.

How much does a space heater cost per month?

At $0.16 per kWh, a 1,500-watt heater used for six effective hours per day costs approximately $43.20 over 30 days.

Does a thermostat reduce electricity use?

It can. After reaching the selected temperature, the thermostat may switch off the heating element. The actual reduction depends on room temperature, insulation, drafts and thermostat behavior.

Is a 750-watt setting half the cost?

Yes, if both settings operate for exactly the same amount of time. However, the lower setting may need to run longer to produce the desired level of warmth.

Is a space heater cheaper than central heating?

There is no universal answer. A space heater can be practical for one occupied room, but using several heaters for long periods may be more expensive than operating an efficient central system.

Calculate Your Own Space Heater Cost

Electricity prices and heating habits vary, so the most useful estimate is based on your own numbers.

Use the calculator above to compare:

Your normal daily use
A lower-power setting
A very cold-weather scenario
A shorter operating schedule
The electricity rate from your latest bill

You can also estimate other appliances with the WattBasis Electricity Cost Calculator.

WattBasis provides educational energy-cost estimates and does not test individual heater models. Calculations do not guarantee savings. Always follow the manufacturer’s instructions and applicable safety guidance.