How to Get Rid of Drain Flies and Maintain a Fly-Free Home

I was once in your shoes. Just another homeowner battling what seemed like an invincible army of tiny, incessant invaders, drain flies. These little pests had taken up residence in my home, turning my quiet sanctuary into their buzzing playground.

Like you, I searched the internet, frantically typing, “How to get rid of drain flies,” hoping for an easy, effective solution. I’ve since waged war on these nuisances and emerged victorious. Now, I’m here to share my experience, offering you a guiding hand as you navigate your own drain fly dilemma.

With a little bit of knowledge, a touch of persistence, and a good measure of determination, you too can reclaim your peaceful home from these pesky invaders. Ready to dive in? Let’s get started.

Understanding the Drain Fly Problem

Drain flies, sometimes known as sewer flies or moth flies, are tiny, fuzzy flies that you’ll most likely spot around your drains. They’re about as annoying as fruit flies that buzz around your overripe bananas. However, unlike fruit flies that you might find in your kitchen, drain flies are more at home in your bathroom, buzzing around the drain.

A few years back, I noticed a peculiar influx of tiny flies in my bathroom. At first, I thought they were the same fruit flies that occasionally invaded my kitchen. I quickly realized that this was a different kind of infestation altogether. What really tipped me off was their breeding ground. They preferred the damp, mucky confines of my bathroom drain to the sweet allure of fruit on my kitchen countertop.

Early Signs of a Drain Fly Infestation

What’s particularly annoying about drain flies is how suddenly they can appear. One day, your bathroom is peaceful, and the next, there are small flies everywhere. That’s precisely what happened to me.

I remember stepping into the bathroom one morning and doing a double-take as I noticed a cloud of tiny flies near the shower drain. It was like a scene straight out of a horror movie! If you start noticing an unusual amount of tiny flies in your home, especially in areas with plumbing fixtures, it’s likely a drain fly infestation.

Potential Health Implications of Drain Flies

Drain flies are undoubtedly a nuisance, but are they harmful? The good news is that drain flies, unlike mosquitoes, don’t bite, and they are not known to transmit diseases. However, in large numbers, they can cause allergic reactions in some people. Moreover, the presence of drain flies could indicate a sanitation problem that should not be ignored.

Identifying the Stages of Drain Fly Development

Understanding the life cycle of the drain fly, or identifying their stages of development, is a critical aspect of successfully getting rid of them. It’s akin to knowing your enemy. The more informed you are about what you’re dealing with, the better equipped you’ll be to tackle the problem head-on. Now, you might be asking, “What does a drain fly look like during its development stages?” This is exactly what we’ll break down in this section.

The life cycle of a drain fly starts from the eggs. Adult drain flies lay their eggs in the nutrient-rich organic matter that lines our drains, septic tanks, and even potted plants. In these environments, the eggs have plenty of food to thrive on once they hatch. I still remember the shock I felt when I discovered that the sludge in my drains was actually an ideal breeding ground for these pests.

After about two days, the eggs hatch into larvae. These are tiny, elongated creatures that vaguely resemble small worms. They have a dark stripe on their backs, making them a bit easier to spot against the grayish muck in the drains. When I first spotted them in my drains, I had to do a double-take. It was like finding an alien species right in my own home!

Drain fly larvae are hearty and can survive in both low-oxygen and high-temperature environments. They spend their time munching away on the organic matter in our drains, growing, and shedding their skin as they prepare for the next stage of their development. This larval stage typically lasts around 8 to 15 days, depending on the temperature and food availability.

Following the larval stage, they enter the pupal stage. Here’s where the magic happens. Encased in a cocoon, they undergo transformation to become adult drain flies. This stage can last from 20 to 40 hours. To be honest, unless you’re watching your drains with a magnifying glass, you’re unlikely to witness this stage.

Finally, the adult drain fly emerges from the pupal casing. Drain flies are tiny – about 1/5 to 1/6 of an inch long. They’re fuzzy, moth-like creatures with a pair of wings that extend out, giving them a unique roof-like appearance when viewed from the side. Adult drain flies live for about two weeks, and in this time, they mate and lay more eggs, continuing the cycle.

Understanding these stages not only helps you identify what you’re dealing with but also guides you in determining the most effective ways to interrupt their life cycle. In the next section, we’ll dive into just that – the various methods to control and eliminate drain flies.

Drain Fly Control and Removal

Here’s where the rubber meets the road. Getting rid of drain flies involves a multi-faceted approach that targets both the adults and their developing young. Based on my personal experience battling these pests, I’ve identified a few tried and true methods that can help you reclaim your home from these drain-dwelling invaders.

1. Manual Removal:

The first step is simple yet effective – manual removal. If you can see the larvae in your drains, take a hard-bristled brush and scrub away. This is labor-intensive but rewarding, as you’re directly addressing the heart of the issue. My first ‘victory’ over drain flies came when I went full Rambo on them with an old toothbrush, scrubbing away at the larvae and organic matter in my drain. The satisfaction of watching them swirl away with the water is hard to describe.

2. Utilizing Cleaning Agents:

Here’s a question I initially had: “Will bleach kill drain flies?” Yes and no. Bleach can kill adult flies and larvae on contact, but it won’t get rid of the eggs or pupae. Therefore, bleach is better for a quick clean-up rather than a long-term solution.

What worked better for me was a mixture of baking soda and vinegar. Pour half a cup of baking soda into the drain, followed by half a cup of vinegar. Let the mixture foam and work its magic for about 15 minutes before flushing it down with boiling water. This method helps clean out the organic matter that the larvae feed on.

3. Commercial Drain Fly Killers:

When the infestation was at its worst, I found solace in commercial drain fly killers. These are products specifically designed to target drain flies and their larvae. They’re generally safe for pipes and effective in reducing fly populations. Just remember to follow the instructions on the package carefully for the best results.

4. Biological Control:

You can also consider biological control methods, like bacterial gel cleaners, which contain microbes that eat away at the organic matter in drains, effectively starving the larvae. This approach takes a bit more time but can be quite effective.

5. Preventive Measures:

Prevention is the best medicine, as they say. Once I got a handle on the drain fly situation, I made sure to regularly clean my drains, removing the organic material that could potentially host a new generation of flies. Keeping the drains dry when not in use also helped, as drain flies prefer moist environments.

6. Calling Professionals:

Finally, if you’ve tried everything and the drain flies still persist, it might be time to call in the professionals. A licensed pest control expert can help identify the source of the infestation and provide targeted treatments.

Remember, the key to winning the war against drain flies is persistence. Keep at it, try different methods, and soon enough, you’ll be enjoying your fly-free home once again. In our next section, we’ll talk about how to deal with stubborn infestations that don’t seem to go away, no matter what you do. Stay tuned!

Dealing with Persistent Infestations

Sometimes, despite your best efforts, those pesky drain flies just don’t seem to want to pack their bags and leave. When I first found myself in this situation, I felt utterly defeated. But don’t lose hope, persistent infestations are tough, but not impossible to handle. Here’s what you can do when drain flies seem to have taken permanent residence in your home.

1. Locate all Infestation Sources:

If drain flies persist, there’s a chance you might be missing a source of infestation. They could be breeding in less obvious places like seldom-used floor drains, under washing machines, or even in certain damp spots outside your home. I once discovered a secondary breeding ground in my basement drain – a place I’d overlooked in my initial cleaning frenzy!

2. Thorough Cleaning:

Ensure a thorough cleaning of all potential breeding grounds. A superficial clean won’t do the trick. You need to get down and dirty to ensure all the larvae and organic matter are completely removed.

3. Regular Maintenance:

Set up a regular maintenance schedule for your drains. Regular cleaning can prevent build-up of organic matter and nip any potential infestations in the bud. After my battle with the drain flies, I made it a point to deep-clean my drains every month.

4. Seek Professional Help:

Don’t be shy about calling in the professionals. Sometimes, an infestation could be stemming from a place that’s hard to reach without special equipment. Professional pest control experts have the right tools and knowledge to help you finally rid your home of drain flies.

Other Drain Pests

While drain flies are the usual suspects when it comes to pests in your plumbing, they’re not the only ones. I once mistook drain gnats for drain flies in my bathroom, only to find out they were an entirely different problem to tackle!

Drain Gnats

Drain gnats, or fungus gnats, are tiny black flies that resemble mosquitoes. They breed in moist, decaying organic matter and are often found in houseplants. They’re not harmful but can be a nuisance, just like drain flies.

Sewer Flies

Sewer flies are just another name for drain flies. The terms are often used interchangeably, though some might refer to larger species as sewer flies. Either way, the removal methods remain the same.


Drain flies may be small in size, but they sure can be a big problem! Having been in your shoes, I understand the frustration that comes with these infestations. But remember, knowledge is power. Understanding what you’re dealing with, their lifecycle, and how to eliminate them effectively are your tools to reclaiming your home. Don’t be discouraged if the first attempt doesn’t rid you of the drain flies. Persistence is key here.

I hope this guide has equipped you with all the information you need to send those drain flies packing. Remember, when in doubt, don’t hesitate to reach out to a professional. Here’s to a fly-free home!

Joxan Williams
Home Maintenance Expert | | Website

I'm a licensed home maintenance contractor with over a decade of experience, dedicated to preserving your home's value. My expertise includes roofing, gutter installation and repair, fencing, pool maintenance, deck and patio construction, plumbing, appliance repair, lawn care, painting, garage doors, windows, sump pumps, and steam heating systems.