PEST CONTROL

Ant Control in Toronto, Oakville & the GTA

Carpenter ants, pavement ants and the tiny ones in the kitchen

Ant control that goes after the nest, not the few ants on the counter. Spraying a trail kills the workers you can see and leaves the queen and her brood in the nest. We identify the species, put bait where the workers will carry it home, and find the damp wood or gap that let them in. For homes and businesses in Toronto, Oakville, Mississauga, Burlington and across the GTA.

Sawdust under a window frame or winged ants at an inside window can mean a nest in the house. Book an inspection.

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AT A GLANCE

Ants at a Glance

Carpenter ant, the one that damages wood

Size: Workers 6 to 13 mm; winged ants up to 19 mm
Colour: Usually black or dark brown; some species part red
Body: Pinched waist, elbowed antennae, six legs
How to tell: Coarse sawdust with dead ant parts below wood
Active: Spring to fall; all winter if the nest is in heated space
Where found: Damp wood: window and door frames, roof edges, porch posts
Bites or stings: Bites if handled, sometimes with formic acid

WHAT TO LOOK FOR

Signs of an Ant Infestation

If you’ve noticed any of these, call and a licensed technician will tell you what it points to.

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Trails of ants along baseboards, counters or the foundation
Large black ants indoors, most often at night (carpenter ants)
Coarse, sawdust-like shavings mixed with dead ant parts below trim, beams or window frames (carpenter ants)
A dry rustling sound inside a wall or door frame
Small mounds of soil or sand between patio stones or along the driveway and foundation (pavement ants)
Many winged ants at an inside window, which most likely means a nest indoors

IDENTIFICATION

How to Identify Ants and Tell Them From Termites

Every ant has a pinched waist, elbowed antennae and six legs. Size and colour narrow it down: ants in Canadian homes run from about 1 mm to 13 mm long, and carpenter ants are the big ones. Crush one and smell it: a rotten smell points to odorous house ants. Then look at where they come from. A trail out of a crack in the patio or slab often means pavement ants. Ants coming out of window trim, with sawdust below it, point to carpenter ants. Winged ants are the queens and males of a mature colony, and are often mistaken for termites, which have been in Toronto since the 1930s.

Flying ant or termite: an ant has elbowed antennae, a pinched waist and front wings longer than its back wings. A termite has straight antennae, a thick waist and four wings of about the same size.
Loose wings on the floor: termite swarmers break their wings off soon after landing. Carpenter ants keep theirs for longer.
Damage in wood: carpenter ant tunnels are smooth and clean inside, with no soil in them.

TYPES

Types of Ants in Ontario Homes

Carpenter ants
Camponotus spp.
The biggest ants in Ontario homes. Workers are 6 to 13 mm and come in several sizes in one colony. The black carpenter ant is black or dark brown; other species can be partly red or brown.
Where found: Moist or rotting wood: window and door frames, skylights, chimneys and porch posts, plus stumps and firewood outside.
The one that can damage the structure
Pavement ant
Tetramorium immigrans
Small, light to dark brown ants with fine grooves on the head and back and paler legs. All the workers in a nest are the same size.
Where found: Under patio stones, sidewalks and slabs, leaving small mounds at the nest entrance. Indoors they come up through cracks in the concrete.
Odorous house ant
Tapinoma sessile
Tiny, 2.4 to 3.3 mm, brown to black, and gives off a rotten smell when crushed.
Where found: Under rocks and boards outside; indoors in wall voids near warmth and moisture, usually heading for sugary food.
Pharaoh ant
Monomorium pharaonis
Very small, under 2 mm (about 1/16 inch), light yellow to reddish brown.
Where found: Inside buildings, in warm, dark spots near hot water pipes, kitchens and bathrooms. Mostly a problem in apartments, hotels and other large buildings.
Do not spray them: sprays can spread the colony into new nests
European fire ant
Myrmica rubra
Red or light brown, 4 to 5 mm. The one that stings, often many ants at once when the nest is disturbed.
Where found: Moist soil in lawns and gardens, and under pots, boards and other objects on the ground. Recorded in Toronto's Don River watershed and the Credit River watershed.
Invasive. Report new sites to the Invasive Species Centre

OUR APPROACH

How We Treat Ants

Step 1
Identify the Species
Carpenter, pavement, odorous house and pharaoh ants eat different foods and nest in different places, so the bait and where it goes change with the species. Pharaoh ants show why this comes first: spraying them can split one colony into several.
Step 2
Bait the Active Trail
Bait is placed on the trail the workers are using, so they carry it back and share it through the colony, queen included. The trail on your counter is the delivery route to the nest. Wiping the trail with cleaner or spraying it after a visit can cut that route off.
Step 3
Find the Nest and the Water
For carpenter ants, the job includes finding the parent nest and any satellite nests, because both have to go or the ants come back. Their nests are in wood that is damp for a reason: a leaking window, roof edge, chimney, eavestrough or porch post. The inspection points to where that is.
Step 4
Perimeter and Entry Work
Outside, a perimeter application along the foundation. You also get a list of what is bringing ants in, such as branches touching the house, firewood against the wall, and cracks in the foundation or slab.

BITES AND STINGS

Do Ants Bite or Sting?

Some do. Carpenter ants have strong jaws and bite if you handle them, and they can inject formic acid into the wound, which makes it sting. European fire ants sting, and when you disturb a nest in the lawn or garden they come out in numbers, each one able to sting more than once. Their stings cause burning, itching and small pustules. A severe allergic reaction is very rare, but trouble breathing or swelling of the face or throat after stings is a reason to call 911. If a reaction worries you and it is not an emergency, call Health811 at 811 to talk to a registered nurse, day or night.

RISKS AND DAMAGE

What Damage Can Ants Cause?

It depends on the species. Carpenter ants are the ones that damage the house: they remove wood to make room for their nests, and because they pick wood that is already damp, a nest often points to a leak or condensation. Pavement and odorous house ants are a kitchen nuisance, going after sugar, grease, pet food and crumbs. Pharaoh ants are hard to clear from apartments and large buildings because their colonies split, and control can take months or even years. European fire ants make a lawn or garden painful to work in.

A few small ants in the kitchen are a nuisance you can often fix yourself; carpenter ants inside, pharaoh ants, or a fire ant nest where people walk need a professional.

CAUSES

Why You Have Ants in the House

Ants come in for food and stay where there is shelter and moisture. A trail in the kitchen is workers going back and forth between a nest and food they have found, and that nest may be outside, under the slab or inside a wall. Carpenter ants are a different case: they choose the house because some of its wood is damp.

What Draws Them In

Crumbs, spills and sweet or greasy food left out
Pet food and pet dishes
Unrinsed containers in the garbage or recycling, and a composter close to the house
Aphids on garden plants and trees, whose sweet honeydew ants feed on
Damp or rotting wood from leaks or condensation
Stumps, logs and firewood near the house

How They Get In

Cracks in the foundation and the concrete slab
Water-damaged window and door frames and hollow porch posts
Branches, shrubs and firewood touching the house

HABITS

Life Cycle and Habits

Habitat

Each species has its spot: pavement ants in soil under slabs and sidewalks, odorous house ants under boards outside and in warm wall voids inside, carpenter ants in moist wood with satellite nests nearby, pharaoh ants near hot water pipes, and European fire ants in moist soil under objects on the ground.

Diet

Most house ants want sugar and grease. Carpenter ants do not eat wood: they feed on dead insects and the honeydew aphids produce, and come inside for meat, sugar and fat. Pavement ants go for greasy and protein foods, including pet food, while odorous house ants prefer sweets.

Life Cycle

A colony starts when a mated queen sheds her wings and digs a chamber to lay eggs. Eggs become larvae, then pupae, then wingless workers. Carpenter ants take at least about 60 days from egg to worker, and a colony needs several years and 2,000 to 3,000 workers before it produces winged ants. Odorous house ant, pharaoh ant and European fire ant colonies have several queens, and pharaoh ants spread by budding: a queen and a few workers carry brood away to start a new nest. That is why treatment aims at the queens and brood, not the workers you see.

Seasonal Behaviour in Ontario

In Ontario, ants are active from spring through fall. Carpenter ant colonies go quiet over winter unless the nest is in a heated part of the building, so ants active indoors in midwinter point to a nest inside. Winged carpenter ants form in summer, stay in the nest over winter and leave in spring or early summer. Pavement ants swarm in spring after rain, sometimes indoors. Pharaoh ants breed all year in heated buildings and mate inside the nest instead of swarming.

PREVENTION

How to Keep Ants Out of the House

Store sugar, cereal, pet food and other sweet or greasy food in jars with rubber seals or snap-tight plastic containers.
Wipe counters and sweep or vacuum often, especially around pet dishes.
Set the pet food bowl inside a shallow dish of water so ants cannot reach it.
Rinse containers before they go in the garbage or recycling, and empty the kitchen garbage often.
Keep the composter well away from the house.
Fix leaks at windows, roof edges, chimneys and eavestroughs, and replace wood that has gone soft.
Trim trees and shrubs so no branches touch the house.
Store firewood away from the house and off the ground, and remove old stumps and logs near the building.
Seal cracks in the foundation and slab where pavement ants come through.
Do not move soil or mulch out of a yard that has European fire ants.

How to Get Rid of Ants: DIY or a Professional?

A few ants in the kitchen you can usually handle yourself. Clean up what they are eating, then use a bait rather than a spray, and give the workers time to carry it back to the nest. Any product you buy should have a PCP number on the label, which means Health Canada has registered it, and you should follow the label directions exactly. Call a professional if you see carpenter ants or their sawdust indoors, winged ants at an inside window, tiny yellowish ants in an apartment, or a fire ant nest in a part of the yard you use.

Flying Ants in the House: What It Means

Flying ants are not a separate kind of ant. They are a colony's winged queens and males, and a colony only makes them once it is mature. Outdoors in spring and early summer they are normal: colonies send them out to mate, and a mated queen sheds her wings and starts a new nest. Indoors is different. Many winged ants at an inside window most likely came from a nest in the house.

Check the antennae, waist and wings first to rule out termites.
Note where they gather, and keep a few in a sealed bag or jar for identification.
Spraying the swarm does nothing to the colony that produced it.

From the blog: Carpenter Ants in a Warming Ontario

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Why Ontario Homeowners Choose Sting Out

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Inspection first, then targeted treatment with registered products used as the label directs. Your technician will advise on any precautions.

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Treatments are applied by technicians licensed under Ontario pesticide rules.

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What GTA customers say

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Sting Out Pest Control helped me get rid of a pretty bad crawling insect problem in my office. They were friendly, easy to deal with, and explained everything clearly from the start. Instead of just spraying and leaving, they came up with a treatment plan that used different methods to get the problem under control. Over time, the infestation was completely gone. I now have them come by once a month for maintenance, and if anything small comes up, they take care of it right away before it becomes a bigger issue. It's been a great experience, and I have peace of mind knowing my office is protected. I would definitely recommend Sting Out Pest Control to anyone needing a reliable pest control company.

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COMMON QUESTIONS

Ant Control: Questions We Get

Why do ants come back after I spray them?

Because spray kills the foragers on the surface and leaves the queen and brood in the nest, so the colony replaces them. With pharaoh ants it can make things worse: contact and repellent sprays can split the colony into new nests. Bait that workers carry back to the nest is what reaches the queen.

How do I get rid of carpenter ants?

Find the nest, and usually more than one. Carpenter ants keep a parent nest with the queen and satellite nests elsewhere, and both have to be treated or the ants return within days or weeks. Then fix the damp wood they chose: carpenter ants rarely move into wood that is dry and sound.

What are the small red ants in my lawn that sting?

In Ontario, most likely European fire ants. They are red or light brown, 4 to 5 mm long, and sting in numbers when the nest is disturbed. They are invasive, nest in moist soil and under objects on the ground, and spread when people move infested soil or mulch. Have the species confirmed before treating, and report new sites to the Invasive Species Centre.

Can I get rid of ants permanently?

Not with spray alone. A lasting fix means killing the colony with bait, then removing what brought it: food left out, damp wood, cracks in the foundation and branches touching the house. Mated queens from outside colonies can still start new nests nearby, which is why the prevention steps matter.

Do you offer a plan for ants?

Yes. You can book a one-time ant treatment, or cover ants under the Complete Ant Protection plan. Pharaoh ants are covered in the Platinum Protection plan.

Sources

Last updated October 20, 2026

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Ant Control Across Toronto, Oakville & the GTA

We treat ants in homes and businesses throughout Toronto and Southern Ontario.

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