11 Effective Ways to Get Rid of Drain Flies in Your Home

Your kitchen is one of the busiest rooms in the house, and you rely on it to make memories and enjoy special times with your friends and family.

The last thing you want is to share your space with drain flies.

Whether they’ve set up shop in the drain of your kitchen sink or your bathroom, it’s natural to want them gone.

This blog will discuss how to get rid of drain flies and keep them from coming back.

What Are Drain Flies?

Drain flies are members of the genus Psychoda. 

These non-biting insects live throughout North America and are common in moist areas that contain lots of organic matter.

In homes, they live in kitchen and bathroom drains. Outside, they’re common in decaying logs, leaves, and compost piles.

Wondering how to identify drain flies? These tiny pests are light gray or tan, with 1.5-5mm long bodies.

They have six legs and one pair of wings and antennae. Their bodies and wings are covered in tiny, long hairs, which make the fly look fuzzy.

Despite the presence of wings, drain flies don’t fly well and are incapable of covering long distances. As such, they tend to live, breed, and feed in the same general area.

When the flies are resting, they fold their wings over their body. Larvae are about 4-10 mm long and legless, with white, nearly translucent bodies and dark stripes down their dorsal area.

What Causes Drain Flies?

Do you suddenly have drain flies in your shower, garbage disposal, or kitchen drain?

Here are a few things that may be attracting them:

1. Moisture

For drain flies to thrive, they need moisture. Drain flies also gather, mate, and lay their eggs in standing water or on moist surfaces.

As such, drain flies are common in sinks with slow or clogged drains. The pests also thrive in drains that aren’t used frequently and collect water between uses.

In fact, the most common place we see drain flies is in the P-traps of inactive sinks. While these P-traps retain some moisture, they become the ideal breeding ground for drain flies. Fortunately, it’s easy to get rid of them by pouring some hot water down the drain.

2. Organic matter

Drain flies feed on decaying organic matter.

While they love the slimy food buildup that collects in drains and garbage disposals, they’re also common in overflow pipes, septic tanks, garbage containers, and rain barrels – essentially any place damp organic material accumulates.

3. Shelter

Drain flies need shelter to live, breed, and lay their eggs. They seek enclosed areas that prevent them from getting crushed and provide the ideal habitat for their eggs and larvae to thrive.

Signs of a Drain Fly Infestation

Not sure you have a drain fly infestation in your home? Look for these telltale signs:

1. Sightings of drain flies

Drain flies are tiny, but you may notice them swarming up from your drain when you turn on the water or use the sink.

Since drain flies are weak fliers, they never range far from where they live, feed, and breed. Look for drain flies in your bathrooms, kitchen, basement, and other locations where moisture and organic matter occur.

2. The presence of drain fly larvae

Although drain fly larvae tend to live in drain traps, toilet tanks, and garbage disposals, you can detect larvae if you look carefully.

We recommend using a small knife to scrape the sides of the drain and check for larvae.

3. Small, dark clusters

Small dark clusters about the size of pinheads could be drain fly eggs. Check for them in damp areas that are difficult to clean, like drains, sub-floor cavities, and drainage channels in your basement or crawl space.

How to Get Rid of Drain Flies

Want to get rid of drain flies in your home? Follow these steps:

1. Unclog your drains

For drain flies to congregate, drains need to offer standing or pooling water and lots of organic matter.

To eliminate their habitat, unclog your drains with a metal snake, or store-bought chemical drain cleaner, or hire a professional plumber to unclog and service your drains for you.

Pros: Will improve the functionality of your drains, will remove drain fly habitat and prevent future breeding

Cons: May not kill existing drain flies

2. Sanitize your drains

Once you’ve unclogged your drains, sanitize your drains and your garbage disposal to remove any drain flies, eggs, or larvae that survived the declogging.

Here’s how:

Start by grabbing a handful of ice cubes and flushing them down your garbage disposal to dislodge scraps of organic material that may be stuck in the blades.

Next, pour boiling water into your garbage disposal, and all your other household drains. This will kill drain flies, eggs, and larvae, without harming your drain or pipes.

You can also make a homemade drain cleaner by mixing half a cup of salt with half a cup of baking soda and one cup of vinegar in a bowl. Pour the solution down your drains, allow it to sit overnight, and follow it with boiling water.

Pros: Will kill all adult drain flies, as well as eggs and larvae, safe, non-toxic, chemical-free

Cons: Unlikely to eliminate heavy buildup of scum in drains. For that we recommend an enzyme bio digester like Invade BIO drain

3. Clean the U-trap

To eliminate drain flies throughout your drain system, make sure you clean the u-trap, as well. Do this by pouring a cup of baking soda down the drain, followed by boiling water.

This will clear any clogs and debris that exist in the drain.

Next, place a bucket under the u-trap, unscrew the slip joint nuts, remove the trap, and use a small bottle brush to clean the drain. Reassemble the u-trap.

Pros: Will eliminate adult flies and eggs living in the u-trap

Cons: Labor-intensive, time-consuming

4. Flush your pipes with an enzyme cleanser

To remove any organic material, eggs, or larvae left behind after the cleaning, pour a store-bought enzyme cleaner (like Invade BIO drain) down your drain.

We love this product since it’s green and eco-friendly.

Instead of harsh ingredients, it contains natural microbes and citrus oil, killing adult flies, eggs, and larvae on contact.

Pros: Effective, long-lasting, suitable for sterilizing and cleaning drains and plumbing 

Cons: Requires regular re-application for maximum effectiveness

5. Use a foaming agent to remove soap scum

Soap scum keeps drains and pipes moist enough for drain flies to breed. To get rid of their habitat, you need to eliminate all the soap scum. The easiest way to do this is by using a foaming agent that digests soap scum.

We recommend Tekko trio foam. This unscented aerosol product is fortified with three potent insect growth regulators, which kill drain flies on contact and prevent eggs and larvae from growing into adult flies.

Pros: Effective, fast-acting, ideal for killing adult flies, eggs, and larvae, helps clean drains and prevents future infestations.

Cons: May contain chemicals or toxic ingredients.

6. Use a contact spray

In addition to the solutions mentioned above, other cleaners on the market can kill drain flies, their eggs, and larvae and can be used to get rid of residual drain flies.

Some of the most effective include Gentrol IGR Aerosol, Pyrid, and PT 565 PLUS .

Gentrol IGR Aerosol is a solution known as an insect growth regulator (IGR), which interrupts the drain fly lifespan, and prevents pupae from becoming adult flies.

Pyrid, on the other hand, is a pyrethrin-based contact spray that kills adult flies.

Another option is Pt565+ aerosol, which also uses pyrethrin to kill drain flies and prevent future infestations.

Pros: These solutions kill flies and their young quickly and can eliminate infestations fast

Cons: May contain harsh chemicals or toxic ingredients

How do Exterminators Get Rid of Drain Flies?

Here’s the process most exterminators follow to get rid of drain flies:

Step 1: Inspection

Because drain flies live and breed in damp, hidden environments like drains and pipes, drain fly extermination services begin with a comprehensive inspection.

The extermination team will evaluate your drains, plumbing, kitchens, and bathrooms to identify drain fly hotspots and pinpoint slow or clogged pipes that provide them with food and shelter.

Step 2: Treatment

Next, the exterminator will deploy drain fly treatment. Most exterminators use chemical methods and habitat modification to kill all eggs, larvae, and adult drain flies (removing food sources, etc.).

Step 3: Follow-up

Since leftover drain fly eggs or larvae can extend an infestation, the extermination team will return to your property after the initial treatment.

They’ll inspect your drains and pipes, identify any remaining signs of drain fly activity, and provide follow-up treatment if needed.

How to Prevent Drain Flies

It’s much easier to prevent drain flies than to deal with them once they’ve infested your space.

With that in mind, here are our most effective prevention tips:

• Run your garbage disposal regularly, and flush it with boiling water at least once weekly.
• Take out household garbage regularly, use cans with lids, and clean garbage canisters with hot water and bleach at least once a month.
• Keep your kitchen sink clean and free of food debris.
• Pick up dirty plates, cups, and utensils promptly, and either hand-wash them or place them in the dishwasher.
• Use caulk to seal any gaps or cracks where drain flies may lay their eggs, like those between kitchen tiles or near bathroom or kitchen sink faucets.
• Install screens in seldom-used drains to prevent drain flies from accessing the area.
• Use the baking soda mixture we recommended earlier in this article to clean your kitchen and bathroom drains every other week.
• Install screens on your windows and doors, fix tears or holes in said screens, and keep your doors and windows closed as much as possible.
• Drain flies love water and sewage, so make sure you remove any areas of standing water in your house and thoroughly clean areas that have been affected by sewage backup.
• Keep drain fly food sources, like fruit and vegetables, in the refrigerator or under a fine mesh fruit cover.

Need a Drain Fly Exterminator? We’re Here to Help

Do drain flies keep coming back? If so, you’re probably at your wit’s end.

Fortunately, you don’t have to live with them forever.

Whether your DIY drain fly removal efforts have failed, or you just want more support, contacting a drain fly exterminator to help can be a great idea.

Fortunately, we have a broad network of reputable partners in your area that can help you eliminate drain flies and reclaim our outdoor space.