Are Space Heaters Safe To Leave On All Night? All you Need to Know

This post may contain affiliate links, which means we may receive a commission if you click a link and purchase something that we have recommended.

Wondering if it’s safe to leave a space heater on overnight?

You’re not alone.

As a home inspector, I get asked this question a lot. So it’s time to explore the world of space heaters.

In this guide, I’ll go over;

  • Space heater best practices
  • Reasons why it might not be safe to leave your space heater on all night
  • Space heaters that can be left unattended for long period.
  • Precautions when using a space heater overnight.

Can you Leave a Space Heater on All Night?

A modern space heater can be safe to leave on all night while you sleep. Ensure the heater has a safety certification label from major testing organizations. To ensure more safety overnight, the heater should have tip over protection, automatic shutoff and an adjustable thermostat.

Space Heater Best Practices

Whether you are present in the room or not, it is not safe to leave space heaters on all night. Space heaters pose several risks, including carbon monoxide poisoning, fires and dry skin.

The best thing to do is to heat your room 2-3 hours before you sleep and turn it off – your room will conserve the heat and still be warm for several hours.

Even if your heater has safety features advertised to prevent unsafe operating conditions, you should still avoid running your heater when you sleep.

Some will tell you that as long as you can be careful and keep things away from your space heater, then it’s safe to leave them on all night.

Others will also base their arguments on the different safety features that come with contemporary heaters.

Features like automatic overheat protection, a cool-touch exterior, a self-regulating ceramic element, or a tip-over safety switch that turns a space heater off if it is knocked on its side are all impressive and dandy.

But can they guarantee your safety when you leave your space heater on all night? NO, you can’t!

3 Reasons Why It’s Not Safe To Leave Space Heaters On All Night

1. Space Heaters Cause Fires

One of the key reasons why you shouldn’t leave your space heater on all night is that it can cause fire.

If you are not aware, the second leading cause of home fires, especially during winter, is heating equipment, according to the National Fire Protection Association.

Space heaters are the most used home heating appliances, which explains why they lead in the number of fires and deaths caused.

The U.S. Consumer Product Safety Commission has reported that more than 25,000 house fires are started by space heaters every year. Additionally, over 300 death cases and over 6,000 people with burn-related injuries that visit emergency rooms every year are partly linked to space heaters.

Almost half of space heater fires start when it tips over or accidentally overheat an object in the room. Most old units can also malfunction or overheat and cause fire in the wiring, especially if you use out-of-date breakers and fuses.

While you can avoid most of these accidents by paying attention and practicing safe space heater use, it’s not worth the risk.

The best thing is to warm your bedroom 2-3 hours before you go to sleep. The warmth that accumulates in the room is usually enough to last through the night. Therefore, you should turn off the space heater and unplug the unit.

2. Space Heaters Emit Carbon Monoxide

The risk of space heaters turning into fire hazards is scary, and most people will do their utmost best to ensure that doesn’t happen.

However, even if you’ve taken all the necessary precautions to avoid space heater accidents that can cause fire, another important thing you don’t want to forget about is carbon monoxide poisoning.

Like many other heating devices, space heaters emit carbon monoxide. If you use your space heater at night, you’re upping the risk of CO poisoning.

The scary thing about CO poisoning is that it’s a silent killer – you won’t smell, hear or see any warning. It’s fatal and kills within a few hours.

Symptoms of carbon monoxide poisoning aren’t something you want to ignore. Feeling short of breath, weak, headache, dizzy, nauseated, vomiting and blurred visions – without explainable reasons – are common side effects you need to look out for.

If you experience such symptoms, go outside immediately. Take a deep breath of the fresh air and see if your symptoms improve. You should also turn off the space heater and let your home air out.

3. Space Heaters Dry Out the Skin

Dry skin seems inevitable in the winter, even when you try loads of moisturizer.

While you might blame the weather for your dry skin, one culprit you might be ignoring is your space heater.

When the mercury drops, we tend to heat our rooms all day and night long. The problem with this is that these heating systems strip the skin of moisture.

Dry skin can lead to other health issues, especially if you start developing cracks.

If you feel your skin is always dry, you need to start running your space heater sparingly. You can also install a whole-house humidifier, or at least consider a humidifying unit for your bedroom. It will provide your skin with much-needed moisture at night. To maintain normal, healthy skin during winter, moisturize before you sleep.

Space Heaters that You can Leave Unattended

If space heaters are not safe to leave on all night, then the question you might ask is if there are space heaters that can be left unattended or what heaters are safe to leave on overnight.

Well, modern space heaters can be left unsupervised for quite a long time because they have safety features that are designed to detect unsafe operating temperatures.

One of the features is an overheat protection that shuts the heater off if the temperature reaches unsafe levels. Another feature is tip-over protection that turns the heater off when it is knocked accidentally.

While these features are great and will help you stay safe, we recommend placing the heater where there is less foot traffic or out of reach of kids and children.

One of the best space heaters that can be left unattended is the Dr. Infrared Heater Portable Space Heater. It has all the features discussed above and ideal for small to medium rooms.

Are Oil Heaters Safe to Leave On Overnight?

Oil-filled radiator heaters are some of the modern space heating units for small and individual rooms. So, are oil heaters are safe to leave on overnight?

As long as they are put in the right position, stable and the thermostat is functioning correctly, you don’t have to worry if it runs overnight. What you want to avoid is placing it next to inflammable objects or close to your bed.

Are Ceramic Heaters Safe to Leave On Overnight?

Ceramic heaters work by passing electricity through the ceramic plate that gets hot with time then radiates the heat into your space. So, instead of the whole unit getting hot, only the inside ceramic plates get hot while the outside plastic casing remains cool.

For this reason, ceramic heaters are safe to leave on overnight because the outside casing remains cool; hence don’t pose any risk to people occupying the room.

Are Infrared Heaters Safe to Leave On Overnight?

Infrared space heaters are not only the cheapest types of heaters to run but also completely safe. They work by first warm the air. When the room temperature is more than the body temperature, the body absorbs the heat, giving you a warm feeling.

Infrared heaters are safe to leave on all night because they warm air instead of heating the object directly. However, it’s still important to take precautions when buying an infrared heater. Most of these heaters’ outer casing is hot to touch, so you want t make sure the heater you choose has all the safety features, including a cool-touch exterior.

Are vented propane and gas heaters safe to leave overnight?

It’s NOT a good idea to leave vented propane heaters on overnight. Some heaters can be left operating overnight, but it best if you turn them off or put a timer so they can run for a couple of hours only.

Are Heaters for Basement Safe to Leave Overnight

Whether you are heating your basement with electricity, natural gas, or propane, it’s not advisable to leave them on at night. If your basement is freezing, we have reviewed the best gas heater for your basement.

Is It Safe to Leave a Space Heater Plugged in?

As you might have realized by now, you can leave your space heater unattended though it’s not something that we’d recommend. Unless the room is freezing and you’re busy working on other things, it’s best if you turn on the heater when it’s essential and turn it off once your desired temperature is reached.

So, is it safe to leave a space heater plugged in? No, it is a fire and electric shock hazard, especially if it doesn’t have adequate safety features.

Remember, heating equipment are the second leading cause of home fires in the United States. You want to make sure your heater isn’t left unattended or plugged in when you are away. Also, plug your unit directly into a wall outlet instead of an extension cord or power strip.

Space heaters also use a lot of electricity, so you don’t want them plugged in or running for a long period of time. Want the most energy-efficient space heaters? We’ve compiled a list of the most efficient heaters for you.

Is It Safe to Put a Space Heater on Carpet?

Where you put your space heater and what you put it on is a critical factor to your safety and those in the room. Putting it in the wrong position or next to inflammable objects poses several risks, including fires, burns, or even deaths.

Is it safe to put a space heater on a carpet? The short answer is no. Placing space heaters directly on carpets or rugs is one sure way of starting a fire in your house because these materials are flammable. They overheat much quickly. You can place your heater on hard floors or any other fire-proof surface like a glass tray.

Precautions to Take if you’ll be Running your Space Heater All Night

Sometimes the cold weather can be too harsh, forcing you to run your space heater throughout the night.

Nonetheless, it would be best if you took some precautions to stay safe.

  • First, make sure your space heater is in excellent condition. Take notice of your electric cords and if there are dings, dents, or any other defects. They could cause an electric shock, fire, or carbon monoxide gas leak, depending on the type of space heater.
  • Keep space heaters clear of combustible materials. It’s recommended that you keep a 3-foot or more perimeter around your space heater. Stacks of papers, plants, blankets, and bedding should not be within reach of the unit.
  • Keep space heaters away from the edge of your bed. No matter how much you want to snuggle up to the warmth, don’t place a space heater next to your bed.
  • Purchase space heaters with tip-over and overheat protection. These safety features can help take a lot of the worry out of using your space heater. A tip- or tilt-over switch will ensure the unit automatically shuts off if it’s tipped over. At the same time, overheat protection will also automatically detect and shut off the unit when the temperature reaches unsafe readings.
  • Plug your space heater directly into the socket. It’s not safe to rely on an extension cord when working with an electric heater. The chance of an extension overheating or causing electrical shock injuries or fires is high and should be avoided. If you have to attach an extension cord, make sure it’s appropriately rated and sized for your space heater.
  •  Install smoke alarms and CO detectors on every level of your home. Be sure to place these detectors outside of sleeping areas and inside each bedroom to guard against carbon monoxide poisoning. Please make sure they’re in excellent condition and working.


It’s important to understand that an electric space heater for homes shouldn’t be used as the primary heat source.

Most of the aforementioned accidents and risks occur because many homeowners use space heaters too much or improperly.

But even if you use them as demonstrated by the manufacturers, accidents and fires can always happen. So, it is good to take all the necessary precautions to limit the amount of damage that can occur.

However, try not to leave your space heaters on at night.

Related posts:

Reasons Why Your Electric Bill So High In The Winter

How Much Propane Does a 30,000 BTU Heater Use?

Are Kerosene Heaters Safe To Breathe?