Have you ever noticed tiny moth-like flies buzzing around your sink, shower, or bathroom drains? These little pests are called drain flies (also known as sink flies or moth flies). While they are not dangerous, they can quickly become a big nuisance in your home.
The good news is that drain flies are easier to remove than most other pests. With a few simple methods and regular cleaning, you can stop them from breeding in your drains and keep your home pest-free.
In this guide, we’ll cover:
- How to identify drain flies
- Natural DIY methods to get rid of them
- Safe cleaning products that work
- Prevention tips to stop them from coming back
- When to call a professional
What Are Drain Flies?
Drain flies are tiny insects, about the same size as gnats (2–5 millimeters). They have fuzzy, moth-like wings and are usually gray or black in color. Unlike other flies, they don’t fly very far. Instead, they make short hops from one place to another.
These flies live and breed in areas with standing water, such as:
- Kitchen sinks
- Bathroom drains
- Shower and bathtub pipes
- Wet basement sinks
- Septic tanks and sewers
- Buckets, mops, or compost piles
Drain flies feed on organic material (slime, grease, or sewage buildup) inside your pipes. That’s why keeping your drains clean is the best way to control them.
Are Drain Flies Harmful?
The short answer is no. Drain flies don’t bite, sting, or spread diseases directly to humans. However, they:
- Can spread bacteria from dirty drains to other areas.
- Multiply quickly, turning a small issue into a larger infestation.
- Cause discomfort and make your home look unhygienic.
So, while they aren’t dangerous, it’s always best to get rid of them as soon as possible.
How to Tell If You Have Drain Flies
Here are a few simple ways to check for drain flies:
1. Duct Tape Test
Place a piece of duct tape over your drain overnight. In the morning, check for flies stuck to the tape. If you find them, you likely have an infestation.
2. Look for Larvae
Drain fly larvae live in the slime inside drains. Remove your drain cover and scrape some of the buildup. If you see thin, worm-like larvae, your drain is their breeding ground.
Natural Ways to Get Rid of Drain Flies
You don’t need harsh chemicals to fight drain flies. These DIY methods are effective and safe:
1. Flush With Boiling Water
Pour boiling water down your drain twice a day for a week. This kills larvae and washes away buildup.
⚠️ Note: Only use boiling water in metal pipes. PVC pipes may get damaged.
2. Scrub the Drain Manually
Use a drain snake or pipe brush to scrub the inside of your drain. Pay extra attention to the U-shaped trap (P-trap), which often holds the most buildup.
3. Soap and Vinegar Trap
Mix water, sugar, apple cider vinegar, and a few drops of dish soap in a bowl. Leave it near the drain overnight. The sweet smell attracts flies, and the soap traps them.
4. Plastic Wrap Trap
Fill a jar with apple cider vinegar, then cover it with plastic wrap. Poke small holes in the top. Flies will enter but won’t escape.
5. Duct Tape Overnight
Seal your drain with duct tape overnight for several nights. Flies trying to escape will get stuck. This works for small infestations.
Using Cleaners to Kill Drain Flies
According to pest experts, never pour insecticides into your drains. They can damage pipes and harm the environment. Instead, use cleaners that break down the organic matter where flies breed.
Traditional Drain Cleaners
Products like Drano or Bio-Clean can clear slime and residue. Always follow instructions carefully.
Enzymatic Cleaners (Safe Option)
These products use natural enzymes to break down organic waste inside pipes. Some popular options include:
- Green Gobbler – Safe for drains, septic systems, and garbage disposals.
- Natural Armour – A gel cleaner that coats tricky pipes.
- American Biosystems – A strong option often used for commercial drains.
How to Prevent Drain Flies
Getting rid of flies is only half the job. To stop them from coming back:
- Flush drains with hot water regularly.
- Avoid leaving dirty mops or buckets of water standing.
- Keep your septic tank and garbage disposal clean.
- Use drain stoppers if a sink goes unused for long periods.
- Watch out for early signs of infestation.
When to Call a Professional
If you’ve tried natural remedies and cleaners but still see flies after a week or two, it may be time to call pest control.
Two of the most trusted companies for drain fly problems are:
- Terminix – Offers flexible plans and decades of experience.
- Orkin – Known for professional service and long-term pest management.
A professional can inspect your plumbing system and find hidden breeding sites that you might miss.
FAQs About Drain Flies
Q: What causes drain flies?
A: They are attracted to stagnant water and organic buildup inside pipes and drains.
Q: How long does it take to get rid of drain flies?
A: Most infestations clear in about a week with consistent treatment.
Q: Will Drano kill drain flies?
A: Yes, but only temporarily. You’ll still need to clean your drains to prevent them from coming back.
Q: Can drain flies go away on their own?
A: No. If the breeding ground (standing water and slime) isn’t removed, they will keep coming back.
Q: Do drain flies come from toilets?
A: Rarely, but they can if the toilet isn’t used often or has a leak.
Final Thoughts
Drain flies may be small, but they can quickly become an annoying problem if ignored. The best approach is a combination of cleaning, DIY traps, and prevention. Start with boiling water and scrubbing, then use vinegar traps or enzymatic cleaners if needed.
If nothing works, don’t hesitate to call a pest control expert. With quick action, you can keep your home free from these pesky flies and enjoy fresh, clean drains.
