Can You Keep a Space Heater Running All Day?

Having a space heater is a great way to keep the winter chill away, especially if certain rooms of your home tend to get cold. But you may wonder if there is a time limit for how long you can run your space heater.

It is safe to leave your space heater on all day as long as you are in the room watching it. You should always shut it off if you plan to leave the room. The only exception is newer space heaters with fancy features like automatic shut-off and tip-over protection.

Before you start leaving your space heater on for 24 hours, however, there are a few things you should know. So let’s look at some crucial aspects of space heaters so you can know when it is safe to leave one running all day. 

Is it Safe to Leave a Space Heater on All Day?

Modern electric heater on floor at home

While it is safe to leave a modern quality space like this one (on Amazon) heater on all day long, this generally only holds true when you can monitor your space heater while it is on. This means you must be in your room with your space heater all day. 

A space heater that is unmonitored is never safe, especially if it is an older model of space heater that runs on propane or has any flame. You also should not leave cheap, top-heavy space heaters on for the entire day as these are more likely to have problems with overheating.

Any space heater made in the last ten years is considered modern. But you should also know how your space heater runs before you leave it on all day.

For example, some space heaters get warm to the touch the longer they are used. This is a sign that this space heater is more liable to overheat when left unattended, and therefore it probably should not be. This is especially true when you have pets or young children in the house who could touch the space heater and burn themselves.

It is also important to consider how easy it is to knock your space heater over while it is left unattended. For example, a desk space heater can be more liable to fall when left alone than one left on the floor. 

How Many Hours Can a Space Heater Run?

Technically a space heater can run for an indefinite period of time. Some space heaters have timers for the maximum time they can be left on before automatically switching off.

Most space heaters also have some overheating protection. Over-heat protection is like a circuit breaker that will flip if the device gets too hot. This can cause your space heater to shut off after it has been on for a long time.

If you leave your space heater running, leave the room, and come back to find that it has shut off, do not attempt to turn it back on until it has time to cool down. The only reason a space heater would shut off without you powering it down is due to overheating or an automatic timer. 

How Does a Space Heater Work?

Space heaters work in one of two ways: radiation or convection. Unlike central heating, space heaters are small and use either of these heating methods to heat a single room. 


A convection space heater works by bringing air into the heater at the device’s base. This air is then heated using ceramic or metal parts, then released from the top, side, and front of the device.

Additionally, most of these devices have fans to help the air as it goes through the heater and is projected into the room. 


Radiant heaters can be compared to sitting in front of a fireplace because they work to radiate heat on all sides of the device. They usually use some form of fuel to heat the air around them. There is no fan in a radiant space heater, and the warm air doesn’t usually travel as far. 

Is a Space Heater Efficient?

A space heater is a small device that can only heat one room, leaving many asking if it is truly an efficient way of heating your home in the winter months.

The truth is, a space heater is not efficient for heating your entire house. However, it is more efficient to heat a room than a fire or stove. 

Many people choose a space heater because they have large homes, and it would be costly to heat the entire thing when they spend most of their time in a single room or pair of rooms (i.e., the home office and living room).

This allows them to just pay for the excess electricity for turning on the space heater rather than needing to pay the expensive gas bill for heating. So if you use a space heater to heat a small portion of your home, it will be an efficient solution. Just not your entire home. 

What Are the Best Space Heaters for Your Money? 

A significant aspect of whether or not a space heater is efficient will depend on the type of space heater your purchase. Some are more efficient than others, and older models tend not to be efficient. Below are the best space heaters for your money. 

Vornado VH200

The Vornado (on Amazon) is a convection space heater that looks like a small fan. Don’t be fooled, though, because this small space heater can blow enough warm air to heat the entire room. It’s a bit on the pricey side but worth every penny. 

Lasko Ceramic Heater

The Lasko Ceramic Heater (on Amazon) is a bit more affordable, but know that it is a convection heater that only blows air in one direction. Therefore you may have trouble getting it to heat an entire room. However, it can be helpful for someone looking for a desk or other tabletop space heater. 

De’Longhi Heater

A De’Longhi space heater (on Amazon) is a radiating space heater that uses oil to function. Although it reaches its maximum temperature more slowly than other heaters on this list, it does a much better job keeping an entire room warm. 

Purchase with caution, however, as these types of space heaters can be warm to the touch and need to be placed somewhere with lots of space in your home.

Lasko Ceramic Bathroom Heater

If you are looking for a space heater specifically for your bathroom, the Lasko Ceramic Bathroom Heater (on Amazon) is the way to go. It runs on electricity and warms up quickly to keep your bathroom nice and toasty.

This space heater is worth the price with exceptional safety features that make it safe for use in the bathroom and other moist areas. 

Where Should I Keep My Space Heater? 

Before you buy a space heater, it’s essential to know that while you can run it all day, you can’t just stick it wherever you want. Several rules come with placing a space heater. They are as follows. 

Not too Close to Furniture

There are many horror stories out there about space heaters catching fire. Most of these occur when a space heater is too close to something flammable. Ensure you plan to keep your space heater somewhere where it will not come in contact with any furniture like a couch or bookcase. 

Do Not Place on Furniture

In addition to not being placed near furniture, you cannot put your space heater on furniture unless it was specifically made for that purpose. This is because space heaters are typically top-heavy, and when placed on furniture, they are liable to wobble and get knocked over–which can lead to a fire. 

Special tabletop space heaters are bottom-heavy and compact, so they can’t get knocked off your table or desk. Read your instruction booklet to find out if this applies to your space heater before placing it on furniture. 

Not Near Pets or Children

Many space heaters are warm to the touch as they warm a room. Unfortunately, small children and dogs typically don’t understand this, meaning they could accidentally touch the space heater and burn themselves.

Never include a space heater in a room where a child is unsupervised. If you have free-roaming pets, you will want to invest in a space heater that is cool to the touch. 

Somewhere Dry

Space heaters can be damaged by moisture. You should never keep them in a bathroom or wet garage where they can get wet. Doing so can cause the space heater to short circuit the next time you turn it on.

Some space heaters are made special for bathrooms. These space heaters are the only ones that can handle moisture and are the only type that can be used in a moist environment. 

Safety Tips and Advice to Know Before Purchasing a Space Heater

Modern electric infrared heater on floor

Now that you know where to put your space heater, it’s time to talk about general safety tips to lower the chances of having a fire or other space heater emergency in your home. 

Plug a Space Heater Directly into the Wall

You may think you are safe by using your space heater with a surge protector, but the reality is that most surge protectors are not built strong enough for your surge protector. It is better to plug your space heater directly into the wall unless you have a construction-grade surge protector. 

Don’t Leave Unattended

Most space heater emergencies happen when space heaters are left in a room unattended, or the owner is sleeping. Therefore it is best to always turn off your space heater before leaving a room. 

If you find this hard to remember, consider investing in a space heater with an automatic timer. While it can be sad to spend the night without your beloved space heater, the night is when most accidents with space heaters occur. 

Give Your Space Heater 3 Feet of Space

No matter where you put your space heater, ensure it is at least 3 feet from anything flammable on all sides. This will lower the risk of anything in the vicinity catching on fire. 

Have a Working Smoke Alarm

Hopefully, you won’t ever have a space heater emergency, but if you do, you must have a working smoke alarm in your space to wake you up before it is too late. 

Watch For Signs of Issues

Space heater emergencies typically happen when a space heater malfunctions. You will always want to look for these whenever you use your space heater. Some signs of malfunctions include:

  • A change in flame color from blue to orange.
  • The space heater turns off on its own (when not on a timer).
  • Sparks.
  • Smoke of any sort.

If you see any of these indications, something is wrong with your space heater, which must be switched off and unplugged immediately. 

Be Cautious of Pets

Not only should you be worried about your pets burning themselves on a space heater, but some pets, namely cats, can be mischievous, purposely knocking over a space heater as part of their playtime. Therefore, if you have a cat, it may be better to avoid a space heater or take additional steps to ensure your cat cannot access your space heater. 

Final Thoughts

Overall, while you can keep a space heater running all day, it is recommended that you do not leave one running while it is unattended, as this can increase the risk of a fire.

Unless you are the owner of a newer space heater that has additional features that protect it from overheating, in that case, feel free to leave your space heater running 24 hours a day!