There are few things more annoying than the high-pitched whine of a mosquito next to your ear at 2 a.m. You turn on the light, it disappears, and the moment you fall asleep it comes back.
The good news is that mosquitoes do not normally live and breed inside Toronto homes. They get in from outside, and a few of them find small pockets of water indoors. Fix both, and the problem usually goes away within a week or two.
Quick Answer
To get rid of mosquitoes in your house, kill the ones already inside, seal the gaps they use to get in, and remove any standing water indoors. If new mosquitoes keep showing up every night, the real source is almost always your yard, and that is where the long-term fix needs to happen.
Why Are There Mosquitoes in My House?
Mosquitoes follow the carbon dioxide you breathe out and the warmth of your body. At night, that trail leads them straight to open windows, doors and any gap in a screen.
The most common ways they get in are:
- Torn or loose window screens
- Doors left open at dusk, including patio and garage doors
- Gaps under doors and around air conditioners
- Attached garages, basements and walkouts
- Hitching a ride on people and pets coming in from the yard
In late summer and fall, some house mosquitoes also look for sheltered spots to spend the winter. Basements, garages and crawl spaces are perfect for them.
Step 1: Deal With the Mosquitoes Already Inside
Start by clearing out the ones you have tonight.
- Close the room and turn on one light. Mosquitoes tend to rest on walls and ceilings near the light, where they are easy to spot.
- Use a vacuum or a fly swatter. A handheld vacuum is quick and works well on high walls.
- Check dark corners. Look behind curtains, under beds, in closets and around bathroom fixtures.
- Run a fan in the bedroom. Mosquitoes are weak fliers, and moving air makes it much harder for them to land on you.
Avoid foggers and “bug bombs” indoors. They spread insecticide over your furniture and surfaces and do little against mosquitoes hiding in corners.
Step 2: Find Indoor Breeding Spots
A mosquito only needs a small amount of still water to lay eggs. Most homes have one or two of these without anyone noticing.
- Plant saucers and self-watering pots
- Vases with flowers that have been sitting for more than a few days
- Pet water bowls that are not refreshed daily
- Sump pits without a tight cover
- Unused floor drains, laundry tubs and basement sinks
- Buckets, mop pails and dehumidifier tanks
Empty, scrub or cover these once a week. In summer, a mosquito can go from egg to adult in about 7 to 10 days, so a weekly routine breaks the cycle.
Step 3: Seal the Entry Points
This is where most of the long-term improvement comes from.
- Repair or replace screens. Even a small tear is enough.
- Add door sweeps to exterior doors and the door between the garage and the house.
- Seal gaps around window air conditioners, vents and pipes with weatherstripping or caulk.
- Keep doors closed at dusk, when mosquito activity peaks.
- Shut the garage door in the evening, especially if it connects to the house.
Step 4: Protect Yourself While You Sleep
While you work on the source, these simple steps help you sleep tonight:
- A fan aimed at the bed
- A fitted mosquito net over cribs and beds, especially for babies
- Air conditioning with windows closed on humid nights
- A Health Canada-registered repellent on exposed skin if you are being bitten indoors, following the label for children
Step 5: Fix the Source Outside
If you clear the mosquitoes inside and new ones appear every evening, they are coming from your yard. Indoor work alone will not solve that.
Check the outside of your home for hidden breeding sites such as clogged eavestroughs, rain barrels and kids’ toys. Our guide to home mosquito treatments that work walks through the full outdoor routine.
If your home backs onto a ravine, creek or stormwater pond, mosquitoes will keep flying in from areas you cannot control. That is why some yards have so many more mosquitoes than others.
When to Call a Professional
It is time to get help when:
- You find mosquitoes inside most nights, even with screens repaired
- Your yard is unusable at dusk
- Your property borders a ravine, creek, pond or wooded area
- Someone in your home has a baby, is elderly, or reacts strongly to bites
A professional mosquito barrier spray treats the shrubs, hedges and shaded areas around your home where mosquitoes rest before they find their way inside. For steady protection all summer, a seasonal mosquito control program returns every 3 to 4 weeks from May through September.
Frequently Asked Questions
Can mosquitoes breed inside my house?
Yes, but only if they find standing water. Plant saucers, vases, sump pits and unused drains are the usual culprits. Without water, mosquitoes inside your home cannot reproduce.
Why do mosquitoes bite me at night indoors?
The house mosquitoes common in Toronto are most active in the evening and at night. They follow your breath and body heat, which is why they find you in bed.
Do plug-in mosquito repellents or ultrasonic devices work?
Ultrasonic devices have no good evidence behind them. A fan, good screens and removing standing water are far more reliable.
Why are there still mosquitoes in my house in the fall?
Some mosquitoes look for warm, sheltered places to spend the winter, such as basements and garages. Seal entry points in late summer to keep them out.
Tired of mosquitoes inside and out? BHT Mosquito Control provides mosquito control in Toronto and across the GTA. Call (416) 995-3383 for a free quote.