Getting rid of house flies starts with cutting off what draws them in. Remove exposed food, keep trash cans lidded and emptied often, and check for moisture around drains and garbage areas since flies need those spots to breed. Seal gaps around windows and doors so fewer get inside. For flies already in the house, sticky traps help with small numbers, but if you’re seeing dozens every day or can’t figure out where they’re coming from, a professional inspection usually turns up a hidden breeding source like food and waste buildup in a drain, a dead rodent in the wall, or a gap in your home’s exterior.
One fly circling the kitchen is annoying. Waking up to a dozen of them every morning before you’ve had your coffee? That’s a problem worth solving. House flies are at their worst across Oregon and Washington from June through September, and once they find a reason to stick around your home, they’re surprisingly stubborn.
Most house fly problems are fixable. The key is getting to the root cause instead of just swatting at symptoms.
Why House Flies Get Worse in Summer
Summer heat works in a fly’s favor. House flies thrive when temperatures sit between 68°F and 86°F, right in the range we see across the Pacific Northwest from June onward. Warm weather speeds up their breeding cycle, which means a small problem can grow into a much bigger one faster than most people expect.
How Quickly House Flies Multiply
Here’s what surprises most homeowners: a female house fly can lay up to 500 eggs in her lifetime, and those eggs can hatch into adults in as little as 7 to 10 days when it’s warm outside. So you can go from seeing three or four flies to seeing twenty or thirty within two weeks. The population isn’t traveling in from somewhere else; it’s growing right on your property.
What Draws Flies to Your Home
House flies don’t show up randomly. They follow smells: food, garbage, decomposing organic material, and moisture. Common attractants include:
- Garbage cans left open or emptied infrequently, especially in summer heat
- Pet food sitting out in bowls between meals
- Compost bins near the back door
- Overripe or bruised fruit left on the counter
- Drains with food and waste buildup
- Pet waste in the yard that hasn’t been picked up
The more of these a home has, the more appealing it looks to a fly hunting for somewhere to land and lay eggs.
Types of Flies You Might Be Dealing With
Not every small flying insect in your kitchen is a house fly. Knowing the type matters because it points directly to where the problem is coming from.
Common House Flies
The classic gray-and-black fly most people recognize. House flies breed in decaying organic material: garbage, animal waste, and compost piles. They’re most active during the day and tend to cluster near food prep areas and windows.
Fruit Flies
Fruit flies are much smaller than house flies, tan or brownish in color, and almost always found hovering around overripe produce, recycling bins, or kitchen drains. They breed in fermenting liquids and soft, overripe food. A fruit fly problem that won’t clear up usually means there’s a moist buildup somewhere, often inside a drain or garbage disposal, that needs to be found and cleaned out.
Drain Flies
Drain flies look slightly fuzzy up close and tend to appear near bathroom sinks, floor drains, and utility areas. They breed inside the film of food waste and grease that builds up in drain pipes over time. If you’re noticing small flies coming out of a bathroom you haven’t used in a few days, drain flies are a likely reason.
How to Get Rid of House Flies: What Actually Works
Getting rid of flies takes more than a single treatment. It’s a process, and the most reliable approach is to remove what’s attracting and sustaining them, cut off entry points, then address active breeding areas directly.
Step 1: Remove Food and Breeding Sources
Start here before anything else:
- Store food in sealed containers and keep counter surfaces clean and dry
- Take garbage out more often in summer, and use cans with tight-fitting lids
- Clean up pet food between feedings rather than leaving it out all day
- Check under and behind appliances for crumbs and spills
- Pick up pet waste from the yard every other day
- Move compost bins further from the house or switch to a sealed composting system
Cutting off the food supply and breeding material gives you the fastest results.
Step 2: Tackle Moisture and Drain Buildup
Standing water and food and waste buildup in drains are two of the most overlooked fly attractants. Pour a cup of water down every drain in your home to confirm water flows freely, and clean out bathroom and kitchen drains with a brush or drain cleaner every few weeks during summer. The same standing water that draws flies also creates mosquito breeding spots around your yard, so fixing drainage does double duty.
Step 3: Seal Entry Points
Flies get inside through gaps. Walk the outside of your home and look for:
- Tears or gaps in window and door screens
- Gaps around utility pipes and cables where they enter the house
- Worn weatherstripping (the rubber or foam seal) on exterior doors. If light comes through, so do flies.
- Small cracks in the foundation or outer walls near ground level
A good rule of thumb: if a gap is large enough to see daylight through it, it’s large enough for a fly.
Natural Scents That Can Help Discourage Flies
Certain scents do a decent job of making entry points less appealing to flies. Basil near a kitchen window, or lavender and eucalyptus near doors, can help cut down on how many flies try to come inside once you’ve already addressed the source. These won’t solve an active infestation, but they help as a supporting step.
What Doesn’t Work as Well as It Looks
Plenty of fly control products do exactly what they say on the label, but they don’t address the actual problem.
Fly Strips and Aerosol Sprays
Fly strips and sprays catch and kill individual flies, but they do nothing about the breeding source. As long as that source is active, new flies will replace the ones you remove. These products are fine as a short-term management tool while you’re working on the root issue, but they’re not a fix on their own.
Store-Bought Bait Traps
Bait traps can reduce fly numbers, but placement matters more than most people realize. Put them too close to the house and you can actually draw more flies toward your entry points instead of away from them. They work best placed well away from the home, near where flies are coming from rather than where you don’t want them to be.
When to Call a Professional for Fly Control
If you’ve cleaned up every visible attractant, sealed entry points, and you’re still seeing flies every day, there’s almost always a hidden source involved.
Signs the Problem Has a Hidden Source
Some patterns point toward something you won’t find with a quick walkthrough:
- Flies consistently appearing in one room with no obvious food source nearby
- A faint smell you can’t quite locate (this often means a dead rodent or food and waste buildup inside a wall)
- Flies coming out of spaces inside your walls or from near the ceiling
- A population that bounces back within days of any cleanup effort
These situations tend to respond poorly to over-the-counter products. The breeding site needs to be found and treated directly.
What Professional Fly Control Looks Like
A professional inspection looks at entry points, drains, spaces inside walls, exterior conditions, and property factors that might be contributing. The treatment addresses whatever the inspection finds: targeted work on actual problem areas, not a generic spray application.
Natura covers fly problems across Portland, Oregon and Vancouver, WA as part of general pest service. If flies keep returning after you’ve addressed the obvious sources, a professional pest inspection usually uncovers what a DIY sweep misses.
Take Back Your Home This Summer
House flies are a manageable problem when you treat them like a process. Start with the source, seal up entry points, address moisture, and if the problem keeps coming back, get help finding what you’re missing.
At Natura, pest control is a process, not an event. That goes for flies the same as any other pest. If house flies are making summer miserable in your home, reach out to our team and experience the Natura difference.