You should not leave a space heater on overnight or in an unoccupied space. However, oil, ceramic, and infrared space heaters are far safer to leave on for long periods than electric space heaters. If you want to keep a space heater on for long periods, avoid using electric space heaters with coils that heat up to an orange glow. These types of space heaters are the most dangerous.
3 Space Heaters that are Safe to Leave on Overnight
If you need a portable heater you can plug into an outlet in order to heat a room, some options are very safe while others are more hazardous. Below are the safest heaters for home use, especially if you have to run the heater overnight.
Oil-Filled Electric Heater
The best choice for heating a room safely is an oil-filled radiator-style heater that plugs into your wall. These heaters are completely silent and produce more heat than competitors. They are constructed so that an electrical element heats the oil inside the heater. Then, the heat radiates from the radiator fins.
- 100% silent operation.
- Never heats up hot enough that it will burn you, meaning it is an extremely low fire risk.
- Heats bedrooms and large spaces more effectively than other heater types.
- Equipped with automatic shutoff, timer, and/or tip-over protection to prevent accidental fires.
Unlike other space heaters—which can be dangerously hot to the touch—a good oil-filled heater never heats up so much that it can burn you when you touch it. This also reduces the risk of fire since the radiator produces steady, safe heat for long periods. Choose a model with automatic shutoff and tip-over protection to increase the safety of this heater. Oil-filled heaters can’t be beaten for silently and effectively heating your room.
Ceramic Space Heater
Ceramic space heaters are a great choice for small rooms where you want safe, reliable heat. They are less hazardous than other electric space heaters. However, even the best ceramic space heater has a higher chance of overheating than an oil-filled heater. So, it’s essential to choose one with overheat protection, tip-over protection, and an automatic shutoff.
- Ceramic heaters are another safe choice for heating a room for long periods.
- There is a higher risk of overheating with ceramic vs. oil-filled heaters.
- Keep your heater 3 feet (90 cm) from flammable surfaces, including carpeted floors.
- Choose a ceramic heater with overheat and tip over protection, as well as a timer or automatic shutoff.
Place your ceramic heater 3 feet (90 cm) from any flammable surface, including clothing, carpet, and paper products. By following these rules, you can use this heater for extended periods. However, as with any heater, it’s best to turn it off when going to sleep, if possible.
Infrared heaters use radiant quartz to produce safe heat that warms an entire room. However, even the best-reviewed infrared heaters have several complaints and negative product reviews. So, while infrared heaters are safer than traditional electric units, they do not get the same positive results as oil-filled heaters or ceramic models.
- Infrared heaters use radiant quartz to heat a room safely.
- Product reviews for infrared heaters are mixed.
- Currently, oil-filled heaters are a better choice for silent, safe, reliable heat.
Although you can experiment with an infrared heater as an alternative to other models, we recommend an oil-filled heater as the best way to heat an entire room. Until our editors fully test an infrared heater, we won’t back it.
Are There Space Heaters You Can Leave Unattended?
You should never leave a space heater unattended. You and your family will be safest if space heaters are only used when there is someone awake in the room. This way, any malfunctions or overheating can be quickly spotted. It’s best to always turn off your space heater when you leave the room or go to sleep.
- It is best to never leave a space heater unattended.
- If you must use a space heater in an unattended space or while you sleep, choose a low-heat model such as an oil-filled radiator.
- Only leave a space heater unattended when absolutely necessary.
- Make sure your space heater has overheat protection, tip-over protection, and a timer. These features prevent dangerous overheating.
If you must leave a space heater in an unattended room for any circumstances, choose a low-heat model, such as an oil-filled space heater. Any space heater that is too hot to touch when it’s operating should never be left unattended. Additionally, make sure your space heater has a timer, tip-over protection, and overheat protection to increase safety.
Are Electric Space Heaters Dangerous?
Electric space heaters—as well as vented propane heaters—are not safe to be used while you sleep. They also cannot be left unattended. This is because these types of heaters can overheat dangerously, increasing the risk of heater malfunction or fire. If you are using an electric space heater, turn it off when you leave the room or when you go to sleep.
- Electric space heaters can be dangerous if used improperly or for very long periods.
- There is a higher risk of overheating if you are using an electric space heater.
- Never leave an electric space heater alone.
- Do not leave an electric space heater running while you sleep.
Despite built-in safety features and certifications, it’s best to avoid space heaters with an exposed electric heating element. These heaters are less expensive than other models but are also less safe. Not only are they a fire hazard to nearby materials, but they can also be a burn hazard when touched.
How Long Can Electric Space Heaters be Left On?
Most modern space heaters can safely be left on for 10 hours or more. However, low-quality heaters are the most likely to cause space heater fires. Choose a reputable model with good reviews. Keep the heater well clear of flammable materials by putting it at least 3 feet (90 cm) from carpet, paper, and cloth. Then, you can safely run your heater for many hours.
Can You Set a Space Heater on Carpet?
Never place a space heater on the carpet, a rug, or any other fabric floor covering. Instead, use space heaters in rooms with wood, tile, vinyl, or composite flooring. If you must use a space heater in a room with carpet, elevate the heater on a non-fabric surface. A desk, table, or chair works great for this purpose.
Is it Safe to Leave a Space Heater On While You Sleep?
Generally, it is safest to turn a space heater off whenever you are going to bed. However, if you must run a space heater at night to remain warm, opt for a space heater with one or more of the following features:
- Use an oil-filled, ceramic, or infrared space heater.
- Choose a model with tip-over protection.
- Make sure your heater has overheat protection.
- Check product reviews to ensure overheating isn’t a known issue.
- Use a space heater with a built in thermostat and/or timer.
- Avoid electric space heaters with hot coils.
- Do not use a vented propane space heater.
By choosing a low-heat space heater with built-in protections, you reduce the chance of dangerous overheating. This will keep you safe even when you use your space heater for long periods of time.