Yes, running a space heater all night is generally expensive. It can add roughly $ 40 to $ 100 + to your monthly electric bill.
Quick Answer: Most space heaters use between 750-1,500 watts of electricity, with the average unit consuming 1,500 watts (1.5 kWh per hour). At the national average electricity rate of $0.17 per kWh, running a typical space heater costs approximately $0.26 per hour, $2.04 per day (8 hours), or $61.20 per month.
Most indoor heaters tend to dry out the air, lowering indoor humidity levels. Dry air can cause irritation to the respiratory tract, leading to symptoms like dry throat, cough, and nasal congestion. For individuals with chronic respiratory diseases like asthma or COPD, low humidity can exacerbate symptoms.
Space heaters
One small space heater plugged in 8 hours a day can add about $50 to your monthly electric bill. Space heaters are a great way to increase the temperature in one room for a short period of time, but keep in mind that they can be costly to run and will result in a higher bill.
Never leave a space heater running for long periods of time, and especially not overnight; it is best to use them intermittently; depending on your situation, a suggested practice would be to turn it off/unplug it for 10 minutes every hour if you depend on its use for longer periods.
Recommended Usage Times
At Night: If you choose to use your space heater overnight, it's best to limit its operation to 4 to 6 hours on a lower setting.
It is not safe to run a space heater overnight. If you use an electric or propane space heater during the day, make sure to protect yourself and your home by following all safety practices. Use space heaters that automatically turn off if they tip over.
It is cheaper to run a space heater only if you are heating a single, small room for a short period (under 4 hours). For whole-home heating or prolonged use, central heating is usually more affordable.
In most homes, Heating and Cooling (HVAC) systems drive the highest energy costs, accounting for nearly 40% to 50% of your total electricity bill. Following these, the appliances that run up your bill the most include water heaters, refrigerators, and laundry machines.
Running a 1500-watt (1.5 kW) heater for 24 hours consumes 36 kWh of electricity. Nationwide, this typically costs between $𝟑.𝟔𝟎 and $𝟖.𝟔𝟒 per day, depending on your local energy rates and how often the heater's thermostat cycles the heating element on and off.
For individuals with COPD, temperatures below freezing (32°F / 0°C) are considered too cold and can trigger severe flare-ups, chest tightness, and shortness of breath. Even temperatures dropping below 40°F (4.4°C) can cause the dry, chilled air to irritate overly sensitive airways.
It takes time for your home to warm up and cool down. If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it.
A COPD flare-up (exacerbation) is triggered by increased airway inflammation, most commonly from respiratory infections (viruses/bacteria), exposure to air pollutants, smoke, and extreme weather. These incidents cause a sudden worsening of symptoms—such as increased coughing, wheezing, and breathlessness—lasting two or more days.
Heating and Cooling
HVAC systems are typically the largest driver of energy costs. Running your furnace or AC more often in extreme weather can exponentially increase your monthly bill. These costs can make up more than half of your total electricity bill.
Heating and cooling (HVAC) systems are the biggest energy consumers in a typical house, accounting for roughly 45−50% of your total electricity usage. Water heaters, refrigerators, and lighting round out the rest of the major draws.
Convection Heaters
They can have wattage from 2000 to 3000W, costing 55p to 83p per hour. This type of heater is best for living rooms and bedrooms with closed air circulation. Larger spaces will require more energy usage and higher electricity costs.
Heating and cooling (HVAC systems)
Heating and air conditioning are the largest sources of residential electricity use in most climates. According to the U.S. Energy Information Administration, space heating and cooling together account for more than 50% of a home's annual energy consumption.
The Top Energy-Draining Appliance: Space Heating & Cooling
This includes both forced-air systems, heat pumps, furnaces, baseboards, window A/C units, and fans. Because they run for long periods and often at high wattage, they dominate the consumption profile.
Natural gas is usually the cheapest way. Even with higher gas prices, a heating system fueled by natural gas is typically less than electricity, propane, or heating oil. Energy efficiency is another way to assess the cost of a heating system. An energy-efficient heating system saves you money on your heating bill.
Avoid overloading electrical outlets with multiple space heaters. Don't use extension cords with space heaters, as they can overheat and cause fires. Don't leave space heaters unattended or running overnight. Consider using space heaters with a thermostat to maintain a consistent room temperature.
The cheapest space heaters to run are low-wattage personal heaters (500W) or heaters with Eco Modes. Because you are heating just your immediate area rather than an entire room, you use less electricity.
The safest heaters to leave unattended are oil-filled radiant heaters (like the DeLonghi Radia S or Pelonis oil-filled radiators) and smart ceramic heaters (such as the Dreo Solaris 718). These appliances use enclosed heating elements and include built-in fail-safes to prevent fires.
You can easily find low-priced, reliable room heaters for small spaces or individual rooms. Top-rated, budget-friendly options typically range from $9 to $35, focusing on portable ceramic, fan-forced, or compact personal desk heaters.
Fire safety experts and consumer protection agencies, including the Consumer Product Safety Commission, strongly advise against leaving a space heater on all night. The risk of a fast-moving fire occurring while you are asleep is significant, as you may not wake up in time to react to danger.