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Why Are There So Many Flies in My House? 10 Possible Reasons (With Pictures)


Many people might say that even one fly is too many, mainly if it’s a biting insect, although one buzzing around your head is equally as annoying. That’s one reason why the insecticide industry raked in $16.58 billion globally. Unfortunately, experts expect it to increase by nearly 40% by 2025 to $22.86 billion. If you have a fly problem, you may wonder how did so many get into your home?

The primary reason for the pests is poor sanitation. Flies are survivors and opportunistic feeders. Scientists also consider them synanthropic organisms. That means they live near humans even if we don’t want them around or have domesticated them. They are found throughout the United States, often holing up in warm places to overwinter.

divider 5 Top 10 Reasons Why There Are Flies in my House

1. Stinky Garbage Cans

Garbage Can
Image Credit: Pixabay

Rotting food in garbage cans is probably one of the primary reasons that flies are getting into your home. Unfortunately, the smell is like putting out a welcome mat for them. The trash attracts them while providing a breeding ground and ready food source for the hatching larvae.

2. Something Rotten in the Yard

Lawn Yard
Image Credit: ArtisticOperations, Pixabay

It isn’t just rotting food luring flies to your yard and house. It can be other foul-smelling things, such as a dead rodent in your home. Pet waste is another powerful reason, making cleaning up the backyard imperative for fly control.

3. Too Many Ways In the House

window stool
Image Credit: evasaves1, Shutterstock

We also have to address the elephant in the room. The reason you may have too many flies is that it’s too easy to get into your house. Even the smallest hole in a screen can provide open access. That applies to keeping a door open while bringing in the groceries. The warmth coming from your home on a cool day will draw them indoors.

4. Available Food and Drink

non-perishable food

Food or drink left out on the counter or table is an open invitation to hungry flies. Bear in mind that an annoyance can grow into an infestation rapidly. A female can lay up to 600 eggs during its short life. They also hatch within 24 hours.

5. Seasonal Patterns

a forest caught fire in summer
Image Credit: valtercirillo, Pixabay

Flies prefer warmer temperatures. That’s why you may not see them in early spring. The summer and early fall are prime times for these pests.  The sudden influx you may see may just coincide with the seasonal weather patterns.

6. The Weather

heavy rainfall and fog on the mountains
Image Credit: rbalouria, Pixabay

That also applies to the temperature spikes you may experience during the year. An unseasonably warm day might bring out the flies and other annoying pests. These insects like dry days, so you’re more likely to see them when it hasn’t rained for a while, unlike the mosquitoes.

7. The Sunny Side of the Street

Sunny house
Image Credit: Pixabay

You may find that the parts of your house getting the morning or afternoon sun is more likely to harbor flies that can get into the house. Making sure that any screens are in good repair is particularly essential for these places.

8. Your Pets

grey rabbit on the carpet
Image Credit: ZouZou, Shutterstock

If you have outdoor pets, your pup may inadvertently bring flies into your house, especially if the yard needs some maintenance. Using a fly repellent can help control the ones tagging along for a ride on your dog.

9. Plants in Your Yard

man planting lettuce
Image Credit: Alexander Raths, Shutterstock

Some plants attract flies because they are pollinators. These species often have a strong scent. Examples include wild ginger, blackberry, strawberry, and mango. These insects are second only to honeybees in the benefits they offer humans.

10. Potting Soil

man holding soil
Image Credit: jokevanderleij8, Pixabay

Potting soil is usually rich with nutrients to give your plants a headstart. It can also provide an ideal setting for fungus and the flies they attract. Remember that’s also the breeding ground with its built-in food source for the larvae.

divider 5

The Problem With Flies

Flies are more than a nuisance. They are intermediate hosts to many parasites that can affect your pets. They also carry harmful human diseases, such as tuberculosis, salmonella, and cholera. That makes getting rid of them imperative for you and your family. The other issue is sanitation since it’s a likely attractant. More often than not, it doesn’t stop at flies.

You may find that some of the things we’ve listed will also bring other unwanted pests to your yard and possibly the house, such as rodents and raccoons. Therefore, you can think of flies as the proverbial shot over the bow that you must take action quickly.

Controlling an Infestation

Several small actions can make a significant difference in the number of flies in your house. We suggest rinsing out your garbage cans regularly to cut down on any odors drawing pests to your home. You can also wait until your trash pick-up day to throw out any perishables that can go bad in the can. If you can keep the bin outside, even better.

Regular cleaning begins in the kitchen. Make it a house rule not to leave out any food or drink that may bring on the flies. Cover any leftovers with tight lids. The same precautions apply to your yard with pet waste. We also recommend checking the garage and walking your yard occasionally for dead animals. Don’t forget to inspect any traps you may have set out for rodents.


divider 5 Conclusion

Flies are more than an annoyance. They are a threat to your health, your family, and your pets. They are vectors for diseases that can cause serious harm. It behooves you to act quickly if you notice an issue. After all, it only takes one insect to wreak havoc. After all, prevention is infinitely easier than controlling an infestation.

Featured Image Credit: Pixabay


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