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How to Get Rid of Sewer Flies in a Bathroom in [year]? [2 Simple Ways]

No matter where you live in the world, you must have dealt with household pests of different kinds. From cockroaches and other bugs to mosquitoes and flies, everyone has had their fair share of putting up with insects and other tiny creatures that cause disruptions in everyday life. 

Bathroom drains often have stagnant water nearby, so it wouldn’t be surprising to find sewer flies there! Unfortunately, these types of flies take less than two days to reproduce. They live for over three weeks, which means that you could be dealing with a terrible infestation if you aren’t careful. 

Thankfully, since sewer flies are small and easier to kill than other household pests, you can get rid of them much more quickly. In this guide, we’re going to show you how to get rid of sewer flies by using natural and chemical-based methods. 

What Are Sewer Flies?

Sewer flies are often called sink flies or drain flies, and in some cases, they are even called moth flies. They look pretty similar to tiny moths, but the only difference between these flies and various others is that they inhabit sewers and drains. Unlike other types of flies, sewer flies cannot fly long distances, so whenever you see one at home, it will usually hop around from one bathroom area to another instead of flying around. 

What do Sewer Flies Look Like?

What do Sewer Flies Look Like

Sewer flies are pretty small. They are no bigger than five millimeters and are generally smaller than two millimeters. They have round, fuzzy bodies and tiny wings that are moth-like. Unlike fruit flies or house flies, these sewer flies have grey or black bodies. They also have light grey wings. When you crush a sewer fly, it leaves behind a powdery substance. 

Where Do Sewer Flies in Bathroom Come From?

Contrary to popular belief, sewer flies don’t come into your bathroom or kitchen through the drains. Instead, these flies breed in the sewer and enter bathrooms through open doors and windows. The sewer flies are often found in bathrooms because the drains contain large quantities of organic matter that these creatures need to survive. 

In addition to bathrooms, sewer flies can often be sound in kitchen sinks, outdoor garden sinks, septic tanks, and even polluted soil containing sewage and other forms of waste. 

What Causes Sewer Flies in Bathroom?

What Causes Sewer Flies in Bathroom

The main reason sewer flies live and breed in bathrooms is stagnant water. 

If you’re trying to distinguish between sewer flies and fruit flies, an easy way to tell the two apart is by identifying where the flies tend to lurk. Fruit flies typically hang around kitchens and basements if they can sense a food source nearby. They hang around rotting fruit and garbage cans. On the other hand, sewer flies hang around areas in a home with stagnant water, such as in bathrooms. Therefore, if your bathroom sink or shower tends to have puddles of water in it, you will find sewer flies there. 

The low puddles of stagnant water allow the sewer flies to breed and lay eggs. When water is stagnant for a long time in a sewage drain, a thin film forms over the water, and the flies lay their eggs there. This is why you will often find sewer flies hovering around your shower or sink drain. 

What Do Sewer Flies Eat?

These creatures don’t have the most delicious-sounding diets! Sewer flies tend to eat sewage and other forms of decomposing matter. They can also find food in garbage dumps, animal waste, and compost sites. Sewer fly larvae eat various forms of fungi and bacteria. In rare situations, they will eat each other. 

Are Sewer Flies Harmful?

Thankfully, sewer flies are not dangerous or harmful. Even though they live and breed in sewers and drains, they do not carry diseases. It’s essential to keep in mind that if a large number of sewer flies enter your home, there’s a chance that they could be spreading bacteria in your bathrooms and kitchen. Therefore, it’s crucial to get rid of them if you suspect an infestation at home. 

How Do You Get Rid of Sewer Flies in Bathroom?

Since these creatures are small and easy to find, it’s easy to get rid of them quickly. Here’s a list of natural home remedies that use products and ingredients you might already have lying around the house. 

Natural Ways to Get Rid of Sewer Flies

Clean your drains regularly

One of the best ways to ensure that you don’t get sewer flies is to clean your drains. It’s easy to forget to clean them, but since sewer flies breed and reproduce in drains and sinks, you need to make sure that you regularly cleanse your drains. Clean your drains using this method at least twice a week. By cleaning out your shower and sink drains regularly, you’re preventing bacteria from building up, and sewer flies from laying eggs near your bathroom. 

Use baking soda, salt, and white vinegar

Use baking soda, salt, and white vinegar

Thanks to this method, you don’t need to look much further than your kitchen cabinets! The combination of baking soda, salt, and white vinegar acts as a natural deodorizer and an exfoliant for your drains and pipes. 

You will need: 

  • Half a cup of baking soda
  • Half a cup of regular salt
  • One cup of white vinegar

This method is simple. All you need to do is pour half a cup of baking soda down the shower or sink drain. Wait for 15 minutes, pour half a cup of table salt down the drain, and pour one cup of white vinegar down the drain. Wait for at least half an hour before using. 

Use liquid dish soap and boiling water

Use liquid dish soap and boiling water

If you don’t have baking soda lying around, you could try removing sewer flies by using dish soap. Some of the best features of dish soap are that it is affordable, easy to find, and can help you get rid of several household pests aside from sewer flies! 

For this method, you will need the following:  

  • Five tablespoons of liquid dish soap 
  • One liter of boiling water

To get rid of the sewer flies, all you need to do is pour the dish soap down the drain. Let the soap sit for about ten to 15 minutes, then pour the boiling water down the drain. 

Use sugar, water, dish soap, and white vinegar. 

The following method involves patience because you need to let the mixture sit overnight. It’s also a great alternative if you don’t have any baking soda lying around. 

To try out this method, you will need: 

  • Half a cup of sugar
  • Half a cup of water
  • Half a cup of white vinegar 
  • A teaspoon of dish soap
  • A medium-sized bowl

Combine all the ingredients mentioned above in the medium-sized bowl or a bowl big enough to hold the liquids. Next, set it on the counter next to your bathroom sink overnight. Ensure that you close the bathroom door and window to prevent the flies from trying to escape. 

The sugar and dish soap scent will attract the sewer flies, and they will drown in the water and vinegar. 

Use apple cider vinegar

Use apple cider vinegar

Even though apple cider vinegar is commonly used in salad dressings, you can also use it to get rid of pests like sewer flies! 

To try out this method, you will need: 

  • Half a cup of apple cider vinegar
  • A tall glass 
  • Some cling film 

All you need to do is pour the apple cider vinegar into the glass and cover the opening with plastic wrap. Then, using a toothpick or a fork, poke holes in the plastic. Make sure that the holes are big enough for the flies to enter through but small enough that they cannot escape. 

The scent of apple cider vinegar will attract the sewer flies. The plastic will trap them, and they will eventually drown in the liquid. 

Use duct tape

Use duct tape

If all else has failed so far, you could give duct tape a shot. For this method, you need to make sure that your bathroom is completely dry so that the duct tape has the chance to adhere to the surface you’re sticking it to. 

All you need to do is cover your sink and shower drains with duct tape. Ensure that you cover the drains entirely with no room for the sewer flies to escape. Once you’ve covered the drains with duct tape, let them remain covered for at least 24 hours. The sewer flies will stick to the duct tape and will be unable to escape. 

By trying out this method, you’re preventing new sewer flies from entering your bathroom and breeding in stagnant water. 

How to Get Rid of Sewer Flies in Bathroom with Chemicals?

Here are two methods that you could try out: 

Use boric acid

Just like in some of the methods mentioned earlier, you need to make sure that your bathroom is completely dry for this method to work. We’d recommend that you don’t use your bathroom for at least 24 hours before using the boric acid. 

Boric acid doesn’t activate when it is wet, which is why your bathroom must stay dry. 

To try this method, all you need to do is sprinkle the boric acid around your shower and sink drains. Boric acid contains potent chemicals that quickly get rid of pests like sewer flies. 

Spray an insecticide down the drain

Your local garden store or supermarket will stock insecticides. Ensure that you read the label and instructions before purchasing an insecticide because you cannot use some of them indoors. 

One of the best features of liquid insecticides is that they are very hands-off. All you need to do is spray the chemicals down your shower and sink drain and in other areas of your bathroom, and then let it work its magic overnight. Insecticides help kill sewer flies and their larvae. 

After you’ve sprayed your bathroom, close the window and doors to prevent any new flies from entering and old flies from escaping. We’d recommend that you spray your bathroom before going to bed. Please ensure that you spray any cracks and crevices that allow sewer flies to enter the bathroom. 

The following day, make sure that you let the bathroom air out for 15 to 30 minutes to dissipate any lingering smells. 

Also read: How To Get Rid Of Serratia Marcescens In The Bathroom

Professional Sewer Flies Control 

While natural methods are often chemical-free and safer for your health, there are times when you need to resort to using chemicals to help get rid of household pests. 

Here are three professional products that can help you control sewer flies: 

Green Gobbler Fruit Fly Goodbye Gel Drain Treatment

Green Gobbler Fruit Fly Goodbye Gel Drain Treatment

While this product works extremely well when it comes to getting rid of fruit flies, the Green Gobbler Fruit Fly Goodbye Gel Drain Treatment helps get rid of drain flies as well! It contains citronella oil, which works wonders against all types of flies and mosquitoes. All you have to do is pour about one cup of this drain treatment down all the drains in your bathroom and wait for it to work its magic. 

It would be best to pour this substance down your drain before going to bed. That way, you can ensure that you don’t accidentally wash it away when washing your hands or taking a shower. You must also ensure that you pour this liquid down all the sides of the bathroom drains to coat the inside of them evenly. 


Terminix is a pest control company that does an excellent job at getting rid of flies, termites, mosquitoes, and rodents. They are based all over the United States, with offices in more than 300 locations; they also service over 45,000 houses every day. When various home remedies fail you, we’d recommend that you get in touch with Terminix. 


Orkin is another pest control service company that can help you eliminate all household pests. Orkin has you covered, from sewer flies in the bathroom to rodents in the kitchen. This company has been around for over a century, with offices in 120 locations all over the country. Getting your home professionally cleared of all types of pests is the best thing that you could ever do! If you are at your wit’s end, then we’d suggest lting Orkin come and get rid of the sewer flies in your home. 

Also read: How To Get Rid Of Centipedes In My Bathroom


How long does it take to get Rid of Sewer Flies?

If you clean your drains regularly and take several active steps to get rid of sewer flies, it takes around one week to get rid of sewer flies. 

Will Sewer Flies Go Away on Their Own?

Yes, they will go away on their own, but only if you kill them as soon as you see them and clean your drains. You risk them coming back and breeding in your drains if you don’t. 

Wrapping Up

In this article, we took you through an extensive list of methods to help you get rid of sewer flies in your bathroom. These flies are a huge pain to deal with every day, but if you take a few simple steps like running hot water down your drains every so often, you won’t have to deal with these flies at all! We also recommended a couple of companies to help you solve the sewer flies problem if natural remedies stop working. Pests like these can cause you to tear your hair out in frustration but can be easily solved with a little care.