What Temperature Do Fleas Flourish In? What is it Fleas Like?

Discover what conditions, like temperature and humidity, lead to the optimal environment for fleas and ticks.

There's lots of talk about "flea and tick season," (in certain circles) but depending on the climate where you live, fleas and ticks may be a year-round concern. That's why it is important to maintain year-round protection with a preventative like Advantage Multi or Nexgard. Discovering the conditions that lead to an optimal environment for fleas and ticks -- like warm temperatures and overgrown bushes -- can help you know when and how to ramp up your preventative measures. And don't miss our flea and tick maps and alerts.


Both fleas and ticks flourish in warm climates. The ideal temperature for these parasites is within the 70 to 85-degree range, but they can live in cooler and warmer temperatures as well. For many states, the most prevalent seasons for fleas and ticks are the spring and summer, or roughly from May through September. For southern and southwestern states, the flea and tick season typically occurs year-round.

Extremely high heat will destroy fleas and ticks, as well as their eggs. If you’re suffering from a flea infestation, washing and drying your pet’s bedding on high heat is a helpful eradication method. Similarly, after being outside in a tick-friendly area, laundering your clothes is a good way to destroy any ticks that may be clinging to your outfit. (Note that ticks have been found to live even after a cycle through the washing machine, so be sure to also dry clothing on high heat.)

Once the temperature falls below freezing for several days in a row, adult fleas will die. However, for fleas in a different stage of the life cycle -- the eggs, larva, and pupa -- the cold weather is not destructive. The non-adult fleas will go dormant, and when temperatures rise again, those fleas will begin to look for a host. Similarly, ticks are only dormant, not dead, when the weather is below freezing. If the temperature rises in the wintertime, be cautious of tick bites just as you would be in the summertime.


Ticks and fleas require a high humidity level, ideally around 70 percent.

The moisture in the air is a matter of survival for ticks: it allows the larval ticks to mature into nymphs. During the nymph stage, ticks feed upon hosts for the first time. Tick eggs and larvae are frequently found in moist organic matter like leaves and brush. As adults, ticks can be found on leaves, bushes, and taller plants. The ticks climb upward seeking potential hosts; when they grow dehydrated, the ticks crawl back down.

Humidity also plays a key role in fleas’ survival: the moisture is necessary for eggs to hatch and for fleas to progress through the life cycle.

Woods, Grass, and Brush

Ticks generally live in the woods, where they can easily find warm-blooded hosts like rabbits, squirrels, and deer. Fleas tend to like dark spaces around homes, like the crawl space or under bushes. Suburban and rural areas are quite comfortable for both fleas and ticks -- you could easily catch fleas in a dog park, and ticks can be present in gardens if there are deer around.

As larva, fleas prefer dark cracks and crannies but as fleas progress through the life cycle, their main goal becomes seeking out a warm-blooded host.


Both fleas and ticks are sensitive to extreme heat and a lack of moisture. Eliminate shaded areas around your home -- keep bushes well-trimmed and mow grass frequently. This will lead to dried-out soil and direct sunlight, which is an inhospitable environment for fleas and ticks.

Residents of warmer climates are unfortunately living in ideal zones for fleas and ticks. Preventative measures -- like applying monthly medications to pets, checking for ticks after being outside, and landscaping outdoor areas thoughtfully -- are recommended to ward off tick bites and flea infestations.

Do I Need to Protect My Pet After Flea Season?

This question could easily have a one-word answer – yes. Yes, we do recommend you give your pet year-round preventative flea and tick medication. Yes, it really makes a difference. And yes, you’ll thank us later.

It is a common misconception that preventative flea and tick methods should only be used during “flea and tick season.” Sure, as the weather turns warmer, fleas have a much stronger presence than during the icy winter months but that doesn’t mean they disappear altogether, especially in warm winters like many parts of the country have experienced. No matter where you live or what the weather is, you need to protect your pet. Pets are like family. You wouldn’t want your toddler to hit the beach without sunscreen, so why would you let your dog run around without their flea and tick armor?

A Stitch In Time Saves… Money

Not only will year-round prevention ensure your pet can avoid having to scratch and claw its way through an incredibly uncomfortable flea infestation, but preventative care is also far less expensive than dealing with fleas once they arrive. Your home can easily become subject to flea eggs, larva, feces, and more. Plus, your pet will be suffering (fleas bites hurt your pets and they can lead to worse damage like tapeworms or even hot spots;  ticks can cause diseases!) and that can easily be avoided.

If you wait for flea and tick season to hit it may be too late. Many oral medications, and even topical treatments like PetArmor, can take months to reach their full effect and actually combat a flea’s full life cycle. The sooner you get started on preventative flea and tick health care, the happier both you and your pet will be. Most medications are taken only once a month and are easily administered so there really is no excuse. Protect your pets year-round. 

Frequently Asked Questions

At what temperature will fleas die?

Fleas can survive extreme temperatures, but they will die if exposed to temperatures that are too cold or too hot for an extended period of time. Fleas are most comfortable at temperatures between 70 and 85 degrees Fahrenheit, and they will begin to die if the temperature drops below 46 degrees or rises above 95 degrees Fahrenheit. However, it is important to note that fleas can still survive in these extreme temperatures for short periods of time, so it may take a while for them to die off completely. To kill fleas effectively, you may need to use a combination of methods, such as freezing, heating, and insecticides.

At what humidity do fleas die?

Fleas can survive in a variety of humidity levels, but they prefer environments with relatively high humidity. In general, fleas can survive and thrive in environments with relative humidity levels between 75% and 95%. Fleas can survive in lower humidity levels, but they may become more sluggish and less active at lower humidity levels. They are also more likely to become dehydrated in low-humidity environments. Fleas can die if the humidity falls below about 50%, as they will be unable to obtain the moisture they need to survive. However, it's important to note that eliminating fleas from your home or yard will depend on more than just humidity levels.

Does humidity make fleas worse?

Fleas are more active and reproduce more quickly in environments with higher humidity levels, so in that sense, high humidity could make flea infestation worse. However, it's important to note that there are many other factors that can contribute to a flea infestation, and humidity is just one of them.

Are fleas more active at night?

Yes, fleas are more active at night. Fleas are ectothermic, which means that their body temperature is influenced by the temperature of their environment. During the day, when the temperature is warmer, fleas are more sluggish and less active. At night, when the temperature is cooler, fleas become more active and are more likely to bite. Fleas are also attracted to the warmth and carbon dioxide produced by their hosts, which can increase their activity at night. In general, fleas are most active at night and during the early morning hours, and this is often when pet parents notice flea bites.

Where do fleas hide during the day?

During the day, fleas often hide in dark, cool places where they can avoid detection and where the temperature is more conducive to their activity. Fleas will often hide in the fur or feathers of animals, such as dogs, cats, birds, or rodents, where they can remain protected and close to a source of food. They can hide in bedding or furniture, such as blankets, pillows, or upholstered furniture, where they can remain protected and close to their hosts. Fleas might hide in the fibers of carpets or rugs, especially in areas where animals spend a lot of time. Fleas can also hide in small cracks and crevices in floors, walls, or furniture, where they can be protected from light and heat. To effectively control a flea infestation, it's important to thoroughly search for and treat all of the potential hiding places where fleas may be hiding.
Related Products

K9 Advantix
Advantage II for Cats
Frontline Plus

More Flea and Tick Control Advice

How to Get Rid of a Tick
Tapeworms in Dogs: How Fleas Can Be to Blame
Will I Overmedicate My Pet if I Mix Flea Meds?

This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis, or treatment by your veterinarian. Always seek the advice of your veterinarian or other qualified professionals with any questions you may have regarding a medical condition. Never disregard or delay seeking professional advice due to what you may have read on our website.

Join our mailing list
Join our mailing list