Can Heat Kill Fleas and Eggs?

  • Written By Dan Edwards on January 16, 2019
    Last Updated: December 30, 2020

We’ve all heard that heat kills fleas but how true is that? If so, what sort of heat do you need?

In this article, we look at different ways of using heat to kill fleas to help you decide if it will be an adequate part of the treatment you perform yourself. A flea-free home is something we all strive towards, so let’s see if heat really helps with that?

Can You Kill Fleas With Heat?

Simple answer – YES!

Fleas need humidity and heat to survive that’s why most flea infestations occur in the summer or spring months across the majority of the US. But like humans, there is a limit to how much heat the flea can handle.

Extremely high temperatures will disrupt a fleas life cycle and kill them at any stage, no matter how big, small, young or old they are.

Fleas cannot survive exposure to temperatures over 95 degrees for prolonged periods. Outdoor fleas often die if for a prolonged period of time in a single month the temperature remains 95 degrees or above.

Using heat to kill fleas can be a cost-effective and environmentally friendly way of ridding your home of those unwanted pests. It’s simply a matter of ensuring the heat is high enough and lasts long enough to kill all the fleas, adult and unborn.

Using heat incorrectly may allow some of the infestation to survive and quickly populate again.

How Hot Does It Need to be to Kill Fleas and Flea Eggs?

Although heating the entire house may seem an option for exterminating the infestation in one quick blow, the high temperatures required make it impractical.

There are instances of people turning their thermostats up to 100 degrees continuously for a period of 48 hours with success. However, most of us do not possess empty homes and trying to live in such extreme temperatures for extended periods would be both uncomfortable and very costly.

To successfully kill all fleas you need a temperature of over 95 degrees Fahrenheit for a minimum of 48 hours.

Flea larvae cannot survive temperatures over 103 degrees for more than one hour. Many flea eggs will survive at the slightly cooler 95 degrees needed to kill adult fleas, with about 40 percent of them hatching.

Flea Larvae
Flea Larvae – CC Image courtesy of Peter J Bryant

Although humidity can also affect the eggs, with 75 percent relative humidity or less causing them to desiccate. If the air is completely saturated the eggs will also die as heat accumulates in the shell.

How to Kill Fleas with Heat

There are many ways you can kill fleas with heat. Some can be quick and convenient while others may be more time consuming and very impractical.

There are commercially available options or professional services that can assist in eliminating an infestation using heat treatments. Let us take a look at some of the more popular methods:


Steam is a completely natural way to kill fleas while cleaning your home at the same time; which is great for those with children looking for a non-toxic solution.

For sofas, carpets, rugs, hard furniture or anything else that may be difficult to tumble dry, a steam cleaner is an ideal solution. Steam kills the flea at any stage of its life cycle including eggs and larvae.

The problems often arise with your choice of steam cleaner. Domestic units kept in homes for cleaning windows and upholstery likely won’t be powerful enough, as you need a constant supply of extremely hot steam. Instead, hiring a commercial steamer is more likely to provide the results you desire without the considerable price tag associated with buying a commercial model.

A steamer may not kill all the bugs on a first application and will require several attempts for maximum efficiency.

However, steam does kill more eggs and larvae than vacuum cleaning and therefore, most definitely worth considering. A recent study suggested a vacuum only removes 40 to 80 percent of eggs in the pile of a carpet and less than five percent of larvae.

If you do choose to attempt steaming, you should be wary of temperatures higher than 180 degrees. Extreme temperatures such as these may damage any fabrics throughout your home.

Flea Eggs On Carpet
Flea eggs in the carpet – CC Image courtesy of Denni Schnapp

Furthermore, unless you have previous experience and feel confident handling a steamer, you could end up burning or injuring yourself too.

Laundering/Tumble Drying

The easiest way to achieve the high temperatures needed to kill the fleas and all eggs is to place your clothing, bedding and any soft furnishings you can into a high-temperature cycle on your washing machine. Followed immediately in the tumble dryer on the hottest setting for at least 30 minutes.

Use the highest temperature and longest wash cycle possible. Moreover, using diluted bleach in water will further aid your efforts.

Fleas are unable to survive in a tumble dryer. Numerous elements will inhibit survival not only the heat itself. The dry air causes desiccation and the rough spinning will lead to physical damage to the fleas and any eggs or cocoons.

Professional Heat Treatment

If you have tried everything else with no success, there are professional treatment options available that don’t use chemicals, just heat. One of the more effective systems is known as Entotherm.

The process works by heating a liquid syrup which is then delivered via insulated pipes to heat exchange units strategically placed in the area to be treated. Thermal imaging technology allows the specialist to ensure the extermination of all the pests.

Although it’s more costly, this system will get very effective results against all household pests, not just fleas. Professional heat treatment can also save you from throwing away any furnishings or carpets that couldn’t be saved by more traditional means.


Heat, if used correctly, can be one of your best friends in the war against fleas. But it is also important that you attack the source of the fleas. If this is a pet, there’s no way you can use heat to exterminate the fleas on them, you will probably end up killing the pet too, which is never a desired method of pest control.

Knowing more about why heat kills fleas may enable you to get rid of the bugs without the need for an expensive contractor. It could also give you more options when speaking to a professional if all else has failed.