Uninvited guests buzzing around your bathroom sink? Those tiny helicopter-like insects doing aerial acrobatics near your drains aren’t just annoying—they’re drain flies, and they’ve made themselves quite comfortable in your pipes.
Don’t panic! While these pesky drain flies might seem determined to overstay their welcome, getting rid of drain flies is entirely achievable with the right approach. These small but mighty nuisances can multiply faster than you can say “pest control,” but armed with some household essentials and a bit of know-how, you’ll have them evicted in no time.
Whether you’re dealing with a few stragglers or what feels like a full-scale invasion, this guide will walk you through everything you need to know about eliminating drain flies and preventing their return. From simple DIY solutions to knowing when it’s time to call in the professionals at BDS Drainage, we’ve got your back.
Drain flies, also known as moth flies, filter flies, sewer flies or sink flies, are those tiny grey or brown insects you’ve spotted hovering around your drains. Despite their name suggesting graceful flight, these creatures are more like tiny helicopters—they hop and flutter from surface to surface rather than soar.
At just one-sixth of an inch long, drain flies might be small, but they pack a punch when it comes to reproduction. A single female can lay up to 200 eggs at once, with new recruits emerging from drain fly larvae every 48 hours. That explains why what started as “just one or two” quickly becomes a small squadron.
These moisture-loving insects are drawn to the warm, humid environment inside your drains, where they feast on the organic matter that naturally accumulates in pipes. Hair, soap scum, food particles, and other debris create the perfect breeding ground for drain flies to set up shop and start their families.
Spotting drain flies is usually straightforward—they’re the small, dark insects congregating around your bathroom or kitchen sinks. However, if you want to confirm the extent of your drain fly problem, try this simple overnight test as your first step in the pursuit of getting rid of drain flies once and for all.
Before bed, place strips of clear tape (sticky side down) over the drains where you’ve noticed activity. Check the tape in the morning—any drain flies attempting to escape will be trapped on the adhesive surface. This method gives you a clear picture of which drains are affected and how serious the infestation is.
Other telltale signs include:
The good news? Most drain fly problems can be resolved within a week using simple household ingredients and consistent cleaning.
Here are five proven methods to kill drain flies:
Start with a thorough cleaning of your sink and drain using your regular cleaning solution. Use a pipe brush to scrub around and inside the drain opening, removing any visible buildup of hair, soap, and debris that might be providing food for the flies.
One of the simplest solutions is also one of the most effective. Boil a medium-sized pot of water and carefully pour it down the affected drain. The hot water helps dissolve organic buildup and can eliminate eggs and larvae. This is not just a great way to eliminate drain flies quickly, but repeating this process once or twice weekly serves as a preventive measure.
For a more thorough cleaning, combine half a cup of salt with half a cup of baking soda and one cup of white vinegar. Pour this mixture down the drain and leave it overnight to work its magic. The combination creates a foaming action that helps break down organic matter. In the morning, flush the drain with boiling water to wash away the loosened debris.
If adult drain flies are still buzzing about after cleaning the drains, create a simple trap using apple cider vinegar. Fill a small dish with the vinegar and cover it tightly with plastic wrap. Poke several small holes in the plastic—large enough for flies to enter but difficult for them to escape. The vinegar’s sweet scent attracts the flies, while the plastic wrap traps them inside.
For persistent infestations, consider using an eco-friendly commercial drain cleaner. These products are specifically designed to break down organic matter without harsh chemicals that might damage your pipes or harm the environment. Follow the manufacturer’s instructions carefully and always flush with plenty of water afterwards.
Sometimes, despite your best DIY efforts, drain flies persist. This usually indicates a deeper issue within your drainage system that requires professional attention.
Consider calling BDS Drainage if:
When drain fly problems persist, the issue might lie deeper within your drainage system. BDS Drainage offers comprehensive CCTV drain surveys that can identify hidden problems contributing to infestations. Using state-of-the-art camera equipment, our experts can locate blockages, damage, or areas where organic matter is accumulating beyond your reach.
These surveys provide a clear picture of your drain’s condition and help determine the most effective treatment approach, ensuring the problem is resolved permanently rather than temporarily masked.
Prevention is always better than cure, and keeping drain flies away requires consistent maintenance and attention to your drainage system.
Establish a weekly routine of flushing drains with boiling water to prevent organic buildup. Monthly deep cleaning with the baking soda and vinegar solution helps maintain clean pipes and eliminates potential breeding sites. Check our blog for more details on drainage maintenance.
Poor drainage creates the perfect environment for drain flies to thrive. If you notice slow-draining sinks, gurgling sounds, or persistent odours, these could indicate underlying issues that need professional attention. Regular maintenance by drainage experts can identify and resolve problems before they become breeding grounds for pests.
After using sinks or showers, wipe down surfaces to remove excess moisture. Fix leaky taps promptly, as even small drips can create the humid conditions drain flies love.
Drain flies might be persistent, but they’re certainly not invincible. With the right combination of cleaning, prevention, and professional support when needed, you can eliminate these pesky visitors and keep them from returning.
Remember, successful drain fly elimination isn’t just about getting rid of the flies you can see—it’s about addressing the underlying conditions that attracted them in the first place. Regular maintenance, prompt attention to drainage issues, and professional intervention when necessary will keep your home drain fly-free.
If you’re dealing with persistent drain fly problems or suspect deeper drainage issues, don’t hesitate to contact BDS Drainage.
Our expert team serves London, Essex, Kent, and Surrey with emergency response capabilities, written guarantees, and 24-hour service. We’re professional, experienced, and offer competitive local rates to ensure your drainage problems are resolved quickly and permanently.
Contact BDS Drainage today for expert solutions that work.
Drain flies themselves don’t bite or sting humans, but they can indicate unsanitary conditions in your drains. According to research by Ohio State University Extension, inhaling dust from dead drain flies may potentially cause respiratory issues in sensitive individuals. More importantly, their presence suggests your drains could benefit from a thorough cleaning.
Drain flies have a remarkably fast reproduction cycle. Females can lay up to 200 eggs at once, and new flies can emerge as quickly as every 48 hours under ideal conditions. This rapid reproduction explains why small problems can quickly escalate into major infestations.
Yes, drain flies can inhabit toilet drains, particularly in toilets that aren’t used frequently. They’re attracted to the organic matter that can accumulate in the toilet’s trap and drain pipes. Regular cleaning and flushing can prevent toilet-based infestations.
This post was last modified on 03/10/2025 11:52
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