How To Get Rid of Gnats

Gnats are a loosely defined group of small flies that includes fungus gnats, fruit flies, and drain flies. In this article, we explain where gnats come from, give step-by-step instructions for effective ways to get rid of gnats, and outline tips to prevent another infestation. For homeowners who want fast results, we recommend the Katchy Duo Insect Trap for treating these pests.

Gnats are tiny flying insects from several families of the order Diptera, which includes larger flies, such as the common housefly, and mosquitoes. Some gnats bite humans, while others are simply a nuisance. 

Common gnat features include the following: 

• Small body—usually one-quarter inch or smaller in length 
• Generally dark-colored 
• Single pair of wings
• Group flying behavior, often in swarms hovering at eye level 
• Diet consisting of plant nectar or blood, depending on type

Typically, gnats will enter your house from the outdoors through cracks or holes in your foundation, walls, windows, or doors.

Gnats often infest trash cans, rotten fruit, and other moist places where decomposing organic matter exists. They can also be found near sinks, drains, and toilets.

Several types of gnats infest lawns and households, including the following: 

Fungus gnats: Fungus gnats thrive in damp conditions and feed on decaying plant matter and fungi. They often inhabit the soil of overwatered house plants. Fungus gnats do not bite, but their larvae can damage your plants, and the adult gnats can be a nuisance.

Drain flies: Drain flies earn their name from their attraction standing water. If water and organic matter collect inside a drain, drain flies will feed on it and multiply quickly. You will most commonly see these gnats in bathrooms and near kitchen sinks. Drain flies do not bite.

Fruit flies: Fruit flies love to feed on fruits and vegetables and can quickly infest homes with easy food access. Other gnats prefer outdoor spaces, but fruit flies are notorious for multiplying indoors. Fruit flies do not bite.

Eye gnats: These gnats live in areas with sandy soil and are especially common in coastal regions. Eye gnats do not bite, but fluid secretions in the eyes attract them, causing significant annoyance to humans.

Black flies: Also known as buffalo gnats, black flies are small biting gnats that nest near small bodies of water. Some people have adverse reactions to black fly bites.

There are multiple ways to get rid of your gnat problem, from traps to professional help. If you have a severe gnat infestation, it may take more than one of these methods to eradicate the pests.

1. Make a DIY Gnat Trap

Trying to figure out how to catch gnats? The most popular option is a vinegar trap, which is simple and cost-effective to create. Simply place a few tablespoons of apple cider vinegar or white vinegar, a few drops of dish soap, and a tablespoon of sugar in a bowl and stir. Set your bowl in an area where gnats are prevalent, such as your kitchen or bathroom. The sugar and vinegar combination will attract gnats, and the dish soap traps the gnats and eventually causes them to drown.

If you don’t have vinegar on hand, a combination of red wine and dish soap can create a similar gnat trap. If your gnat infestation is particularly intense, you may want to set out a few bowls of this wine trap mixture around the house.

Finally, a fruit trap can prove effective. Homeowners can cover a jar of overripe fruit with plastic wrap and poke small holes into the wrap’s surface. The gnats will smell a food source and enter the jar, becoming trapped.

2. Use a Spray

If you have a smaller pest problem, a simple spray bottle of one tablespoon of vinegar and a small amount of dish soap may be enough to treat your issue. If gnats are hovering around houseplants or crawling in your potting soil, the issue is likely due to overwatering. To treat this type of gnats, spray a gentle insecticide, such as neem oil or dish soap diluted in warm water, onto the plant. If you use dish soap, you’ll need to carefully wash the solution off after two hours.

3. Bleach Your Drains

If you notice gnats around your kitchen sink or bathtub, pour a cup of diluted bleach down the drain to kill the gnats. Be sure to pour the cup of bleach down each drain or garbage disposal very slowly until there are no more gnats in your line of sight.

4. Make a Candle Trap

Place a candle in a candlestick and fill the holder partially with water. Light the candle and turn off the lights. The gnats will flock to the flame and be burned or will fall into the water and drown. Obviously, this trap is less convenient than a wine or vinegar trap, and you’ll need to remember to blow out the candle before falling asleep.

5. Buy a Glue Trap 

Glue traps, or sticky traps, are strips of paper or tape with an adhesive coating that traps gnats. You can set these traps anywhere in your home that sees gnat activity. The traps will need to be replaced often and may have limited effectiveness for large infestations.

6. Install an Electric Insect Killer

You can purchase an electric insect killer, or bug zapper, to install on your porch or patio. These products kill gnats with an electric charge when they fly into the device. Bug zappers are an excellent way to deter biting gnats in your yard but will not fully eliminate their population.

7. Hire a Professional Pest Control Company for Gnat Extermination

If you have a lingering gnat infestation, a professional pest control company can help address it. The best companies have expertise in treating gnat larvae and adult gnats and will create a customized treatment plan for your home at a reasonable cost for pest control.

Once you have treated your gnat infestation, there are a few tips to help prevent a future infestation.

1. Clean up food and drinks after meals: Don’t allow food or drinks to sit out after meals and clean up any food or drink spillages shortly after they happen.
2. Take out your trash every night and use a sealed trash can: Gnats are often attracted to items in the trash. By using a sealed kitchen trash can and emptying your trash can nightly, gnats will be less likely to enter your home and gather around your trash.
3. Water plants with less frequency: Only water your indoor plants when necessary. If you overwater your plants, gnats may use the area for moisture and to lay eggs.
4. Put fruit in your refrigerator: Because gnats are attracted to the smell of fruit, leaving fruit exposed on your counters can attract gnats. Place your fruit in the refrigerator instead of leaving them out.
5. Remove humidity inside and outside your home: Homeowners should repair plumbing leaks and sink drain stoppages. To prevent outdoor gnat problems, clean up any damp areas around rain gutters and birdbaths.
6. Set up preventive yellow sticky traps: Place these near any trouble areas, such as near ripe fruit or houseplants, to keep an infestation at bay. We recommend trying GreenKeeper’s Stick Traps.
7. Keep your drains clean: Perform regular drain maintenance with diluted bleach or a specialized cleaning solution to keep them free of food particles and fungus gnat larvae.
   For a more eco-friendly drain cleaner that targets gnats, drain flies, and fruit flies, opt for a product like Natural Armor All-Natural Drain Fly Killer or Green Gobler Fly Goodbye Drain Treatment.
8. Don’t overwater plants: Indoor plants are often home to gnats, and overwatering them leads to damp potting soil that’s the perfect breeding ground for an infestation. Ensure your plants are in a pot with a drainage hole and cut back on your watering schedule if you notice gnats buzzing around your houseplants.
   Since they can also carry gnats into the home, check any new plants thoroughly for gnats before bringing them into your household.

Homeowners who wish to save time and frustration can work with a professional pest control provider. The This Old House Reviews Team evaluated every major pest control company in the industry and found that Terminix and Orkin provide the best service to homeowners across the country.

Both of these companies will implement a customized treatment plan for your home and educate you on ways to prevent a future infestation. We always recommend getting quotes from at least two companies to ensure you’re getting the best price on your service.

The This Old House Reviews Team backs up our pest control recommendations with a detailed rating methodology that we use to objectively score each provider. We review pest control plans, navigate the provider website, speak with customer service representatives by phone and online chat (if available), request quotes, and analyze customer reviews for each provider. We then score the provider against our review standards for plans and services, reputation and customer responses, customer service offerings, workmanship guarantees, financing, and availability to arrive at a final score on a 5-point rating scale.

To share feedback or ask a question about this article, send a note to our Reviews Team at reviews@thisoldhousereviews.com.