Flies typically come inside homes by gaining access through damaged screens, cracks in the foundation, open doors, or open windows. Other times, flies may have bred inside, coming in on stored produce or the soil in potted plants. 

Fortunately, you can often get rid of indoor flies through environmental changes. Here’s how to identify, locate, and deter flies from becoming a nuisance inside your home. 

WHY ARE THERE SO MANY FLIES IN MY HOUSE ALL OF A SUDDEN?

Sometimes it can feel as though an infestation has cropped up overnight. Why the sudden increase? The quickest reasons tend to be:

• Flies breeding on improperly stored food or in open garbage that hasn’t been taken out.
• Flies coming in as eggs or larvae in new houseplants and then emerging.
• Flies discovering open windows or doors that allow them easy access indoors.

If flies get inside, there is a chance that they could find a habitat worth breeding in. If so, they’ll start to multiply. Even if you didn’t have a problem at first, you may find that the number of flies inside your home is growing.

WHAT FLIES ARE INSIDE MY HOUSE?

Here are four of the most common types of flies found in homes and how you can identify them if they’re inside yours. 

HOUSEFLY

WHAT DOES IT LOOK LIKE? 

The common housefly (Musca domestica) is a relatively large fly, around 6 to 7 mm long. Female houseflies are usually larger than males and have wider gaps between their eyes. 

On a fruit fly’s thorax, they have four black stripes. Overall, these flies look black, but they do have some color variation if you look closely.

WHERE DOES IT LIVE?

Houseflies live all over the world in a variety of climates. Interestingly, they only live for a short time, around 15 to 25 days. In some cases, they can survive around two months. 

Kitchen waste creates a preferred habitat for breeding. Houseflies will also live in fermenting vegetable matter or in cow manure. 

BEHAVIORS TO NOTE

Houseflies normally go dormant at night. You can typically find them in high places, like on top of your cabinets or on ceiling beams.

FRUIT FLY

WHAT DOES IT LOOK LIKE? 

The common fruit fly (Drosophila melanogaster) is normally yellow or tan. It may appear brown or black until you get close to it, though. They normally have red eyes, but some variants do have white eyes. 

Fruit flies only get up to around ⅛ inches in length. 

WHERE DOES IT LIVE?

Fruit flies live all over the world and are considered nuisance pests. They come in from outside and also breed inside if the conditions are right.

BEHAVIORS TO NOTE

Fruit flies lay their eggs in fermenting or over-ripened fruits, vegetables, or other organic materials. 

FUNGUS GNAT

WHAT DOES IT LOOK LIKE? 

Fungus gnats (Bradysia spp.) are small black flies that get up to around ⅛ inches long. Their forewings have a “Y” shape, and they look similar to mosquitoes.

WHERE DOES IT LIVE?

Fungus gnats generally breed in houseplants. As larvae, they’ll eat organic materials like plant roots, fungi, and algae. 

BEHAVIORS TO NOTE

These gnats don’t lay their eggs very deeply, so you’ll normally find larvae within the first few inches of whatever the plant’s growing medium is (soil, for example). 

Adult fungus gnats don’t bite, and they live around 10 days.

CLUSTER FLY

WHAT DOES IT LOOK LIKE? 

Looking very similar to the common black housefly, the cluster fly (Pollenia rudis) is a slow-flying, attic-dwelling insect. They are primarily black and don’t have as many stripes as the common housefly.

WHERE DOES IT LIVE?

Cluster flies like to live in attics or around siding or windows that offer protection from the elements. 

Eggs are normally laid outside. They are often found near the openings of earthworm burrows. The larvae, after hatching, go into the burrow to feed on the worms inside. 

When cluster flies live inside in the winter, they usually begin moving outside in the spring. 

BEHAVIORS TO NOTE

Cluster flies are fairly active flies. In the summer, you may see them near the ground. They may also congregate around electrical fixtures or window frames as temperatures cool down. 

Remember, you don’t have to know what kind of flies are in your house to call our experts at Joshua’s Pest Control. Our experts are trained in pest identification and are always happy to help.

HOW DO I FIND OUT WHERE FLIES ARE COMING FROM IN MY HOUSE?

Do you keep your trash cans in your garage? Are you using a tabletop compost bin indoors? Do you have plants outside on a screened-in patio? All of these places could be hiding spots and habitats for flies.

Most of the time, flies live in organic materials. Check for flies in places like the soil around houseplants or in your trash. They’re also commonly found in bathrooms or in areas around or inside drains. 

You should also check for gaps along your house’s foundation, windows, and doors. Identifying cracks or holes can help you find where insects are getting into your house. If you do find openings, you can seal them up using caulk, foam, weather stripping, or door sweeps, depending on the location of the gap. 

HOW DO I GET RID OF A FLY INFESTATION IN MY HOUSE?

There are several different methods you can use to get rid of fly infestations in your house. Try these ideas to get started. 

ELIMINATE FOOD SOURCES

If you want to control indoor flies, you have to cut off access to trash cans and compost in the home. Clean up food immediately, keep food in sealed containers, and regularly clear your garbage disposal. 

TRY MANUAL ELIMINATION

If you only see one or two flies here or there, a good ole’ fashioned fly swatter can do the trick. If there isn’t an infestation yet, but a few flies are inside, getting rid of them this way can prevent further issues. 

ELIMINATE SEWAGE ISSUES

Since many kinds of flies breed or spend time around feces or manure, you need to make sure any sewage issues aren’t impacting your property. Flush all toilets and keep bathrooms tidy. If there is a sewage backup or problem outside on your property, call your sewage company or a plumber as soon as you can. 

GET RID OF (OR QUARANTINE) HOUSEPLANTS

Many flies breed in soil or in moist organic material, so it may help to get rid of houseplants until the issue is resolved. If you don’t want to get rid of your plants, consider isolating them outdoors to let the flies naturally leave. You can alternatively keep the plant indoors within a plastic bag to prevent the flies from coming out. Be sure to put tiny punctures (smaller than the flies) through the plastic to allow the plant to get enough carbon dioxide and sunlight. 

As the flies or pests hatch, they won’t be able to escape. Within a few days, you’ll be able to tell if the plant you’re quarantining is the one with an infestation or if the culprit is somewhere else in the home.

REACH OUT TO JOSHUA’S PEST CONTROL FOR HELP WITH FLIES

Need help getting rid of flies inside your home? Contact our field experts for assistance locating hard-to-spot sources of infestations and to get your house back to normal. Give us a call today to get a free quote for the right pest control plan for you.

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SOURCES

• https://entnemdept.ufl.edu/creatures/urban/flies/house_fly.htm# 
• https://www.sanbi.org/animal-of-the-week/common-fruit-fly/
• https://entomology.ca.uky.edu/ef621
• https://extension.colostate.edu/topic-areas/insects/fungus-gnats-as-houseplant-and-indoor-pests-5-584/
• https://extension.unh.edu/resource/cluster-flies-fact-sheet 

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AUTHOR BIO

Courtney Enzor has worked in the pest control industry for about a decade. From helping you build a fly trap to giving you the best tips for identifying various bugs, she loves answering all your pest-related questions and sharing her pest-related expertise through writing. At the end of the day, she hopes her content will help people avoid mishaps and keep families happy and healthy!