Leaving Tumble Dryer On Overnight: Is It Safe Or Should You Worry?

A tumble dryer is convenient for drying your clothes anytime and automatically, providing the required warmth and air to dry them quickly. But is it okay to leave the dryer unattended or run overnight? Are there any risks to be concerned about?

Leaving a tumble dryer overnight is safe if the device has modern safety features to protect the machine from overheating or malfunctioning. Older appliances do have a higher risk and should only be used unattended when serviced regularly and with external safety measures (fire & CO alarm) installed.

We will take a look at the risks, give advice what you should do, and answer the most common questions.

What Will Happen If I Leave My Tumble Dryer On Overnight? 

Leaving a tumble dryer on overnight can have several negative impacts concerning the safety of the appliance and the quality of the drying process. These include:

  • slightly higher risk of unnoticed fire
  • drying result unsatisfactory
  • mold (if clothes are still wet)
  • crumpled clothes
  • slightly higher energy costs (wrinkle protection)

To reduce these risks and avoid negative outcomes you should adhere to best practices. We have comprised these into some easy Dos and Don’ts.

Tumble Dryer Safety Advice – Dos and Don’ts 

Here are a few easy steps that can significantly improve your tumble dryers safety:


  • Unplug your dryer when not in use.
  • Regularly clean filters after every load for optimal efficiency and safety.
  • Keep the area around your dryer clean and free of clutter.
  • Don’t leave your old dryer running while you’re not home or when you’re sleeping.
  • Routinely ensure the vent pipe is connected correctly and runs directly outside (when using a vented dryer)
  • Inspect your clothes to be sure they’re well-suited for machine drying before adding them to the load.
  • Do always make sure the door of your dryer is closed when you are operating it.
  • Do keep flammable items away from your machine.
  • Check your cables and outlets that provide electricity to the dryer


  • Don’t put things like rags, mops, linoleum, foam rubber, or anything flammable in your dryer unless they have been thoroughly dried from flammables before being added to the load.
  • Don’t leave laundry items in the dryer overnight or for an extended period.
  • Don’t forget to periodically check the outside vent flap to ensure it works correctly and opens effortlessly.
  • Don’t dry items overnight that need to be air dried after machine drying (see manufacturers’ advice)
  • Don’t dry unsuitable items at all
  • Don’t leave children unsupervised around a tumble dryer.

Safety Risks When Leaving Tumble Dryers Unattended

After having good guidelines to operate a tumble dryer as safe as possible and efficient, here are the most relevant risks when something goes wrong:

Fire Hazard

A malfunctioning dryer has the potential risk to cause an unnoticed fire when left on overnight. Tumble dryers are using heat elements and have strong motors that convert a lot of energy. A disturbance in this process could lead to a fire.

This risk is well-known by the manufacturers and decreased in modern devices with several safety features to shut off the dryer when something goes wrong. This includes overheating protection, electricity problems, and balancing issues.

The risk of fire is increased in old devices that don’t have these safety guards.

Nevertheless, the overall chance of having a fire from a tumble dryer is relatively low.

Statistics state that a fire caused by a tumble dryer happens only 2,900 times a year. With approximately 120 million households in the U.S. and a tumble dryer rate of 50%, we can assume 60 million tumble dryers are running. When applied once in two days the risk of fire for 1 usage is 0,00000000936 %.

How to Prevent?

To prevent your tumble dryer from catching fire, make sure the machine is serviced well. Its lint trap should be cleaned regularly so that no lint or debris accumulates inside the machine.

Carbon Monoxide Poisoning (Gas-powered Dryers)

Carbon monoxide develops when unclean combustion exists. This can occur during a fire or when a deliberate combustion malfunctions. While the fire is a risk per se, gas-powered dryers could be a problem if the exhaust vent doesn’t work properly or the combustion is erroneous.

How to Prevent?

The best way to avoid carbon monoxide poisoning is by using a tumble dryer without combustion. This old method is inefficient and includes some unnecessary risks.

If you have a gas-powered clothes dryer in your home, ensure it has a proper exhaust system. Do regular service and check your device every time of use.

Install a carbon monoxide alarm that will inform you in case of any dangerous development of the odorless and colorless gas.

Electric Shock

A tumble dryer without sufficient safety features could overheat when left on overnight and result in damaged cables and other components. When the grounding is impaired too, this could lead to an electric shock.

Read our full article on electric shocks from tumble dryers.

How to Prevent?

To prevent this, you should always unplug your tumble dryer before bed. If you don’t have an automatic switch that turns off your machine when it’s not being used, you will need to turn off the power supply manually.

Regularly check your device for any possible failures and conduct the suggested service.

Is It Ok To Leave a Tumble Dryer On When Out?

Leaving a tumble dryer on when out does have some negative aspects but is generally okay if the appliance has modern safety guards and is serviced well. The remaining downsides comprise mainly performance reductions and are not crucial for safe utilization.

If you still have an old dryer that has very few or no safety features the general risk of malfunctions and catching fire is slightly increased. We’d suggest operating those appliances not unattended.

The mentioned performance reductions should be considered when thinking about leaving the dryer on. If your shirts are wrinkled too much after several hours in the finished dryer the process didn’t have much value.

What Happens If You Leave Clothes In The Dryer Too Long?

Leaving clothes in the tumble dryer is possible, but can have several negative impacts:

  • Crumpled clothes
    Dried clothes settle down in the tumbler and are folded in many random ways. They are weighted down by the items above and in combination with the remaining heat in the dryer that functions like soft ironing and results in wrinkles.
  • Developing mold
    The drying program ends when the instructed sequence is finished. The remaining humidity of the items varies and can lead to moist clothes in the dryer. When left in the dryer for too long, mold can rise.
    Remaining humidity can be prevented when using sensor-controlled tumble dryers.
  • Drying result unsatisfactory
    The remaining heat in the dryer interacts with the clothes and dries them continuously. This can result in too-dry items or even shrinkage.
  • Energy costs are slightly higher
    Many modern tumble dryers include wrinkle protection that automatically spins the tumble periodically to reduce the weight on the items and change the folding. The energy costs rise slightly (but are worth it).

Is It Bad To Leave Dry Clothes In The Dryer?

Leaving clothes in the dryer is not bad, because the disadvantages only concern some minor problems if the dryer is equipped with wrinkle protection and a sensor for the drying process. Utilizing a tumble dryer without any of the mentioned features is not ‘bad’ but should be avoided to prevent wrinkles and rising mold.

How Long Can You Leave Dry Clothes In The Dryer?

Clothes can be left in the tumble dryer for a prolonged time if the appliance is equipped with wrinkle protection and a sensor for the remaining moisture. Devices without those tools should be emptied as soon as possible, to prevent wrinkles and mold.

In general, we suggest removing dried clothes as soon as possible.

If necessary you can leave the items in the tumble dryer for several hours, depending on the features available. We have comprised our experience in the following table:

Dryer featuresReasonable delay
Dryer with sensor0 – 4 hrs*
Dryer with wrinkle protection4 hrs
Dryer with sensor and wrinkle protection24 hrs
Dryer without sensor and wrinkle protection0 hrs

* – A dryer with sensors can dry the clothes very satisfactorily. The time in the finished dryer depends on the sensitivity of the items. Towels can be left 4 hrs in the tumble and shirts should be removed immediately.

Frequently Asked Questions 

Here are a few frequently asked questions to clear your doubts: 

How To Know If Your Tumble Dryer Is Overheating?

If you take your clothes out of the dryer and notice burn marks, this is a sign that your tumble dryer is overheating. 

Overheating is dangerous because it can lead to a fire. Thus, it is advised to get your tumble dryer checked if you see any signs of overheating in your machine. 

How Long Does It Take For The Tumble Dryer To Cool Down?

Cooling down a tumble dryer after a wash is not as quick as it sounds. The process takes about 5-10 minutes, depending on the type of tumble dryer you have.

Can a Tumble Dryer Catch Fire When Turned Off?

If your tumble dryer has some electrical system issues, it can cause an electrical shock in its wiring and other components, even if it’s turned off. This could result in your tumble dryer causing a fire. 

Before You Go

After reading this article, we hope you have a clearer idea about the risks associated with leaving your tumble dryer on overnight. If you service your dryer and do have a device with safety features the risk to catch fire is very low.

Nevertheless, you must follow the manufacturer’s instructions. Doing so will follow the safest, most secure way to operate your tumble dryer.