How to Get Rid of Red Ants and Fire Ants: A Canadian Guide for Homes and Yards

TL;DR

• First, name the ant. Red ants indoors are often small house ants such as pharaoh ants, while red ants that sting in the yard are usually European fire ants.
• Indoors, put slow-acting bait right on the ant trail, out of reach of children and pets, for at least two weeks, and don't spray while you bait (Health Canada).
• Outdoors, cover up with gloves, boots and pants tucked into your socks, then apple slices laid about 1 metre apart can help you find hidden fire ant nests.
• Baits with 2% boric acid in sugar can reduce fire ant numbers but won't wipe out a colony. Nest treatment with a registered insecticide is often used for small to medium infestations (Metro Vancouver), and Health Canada notes it may eliminate colonies.
• Stung? Step away and brush the ants off fast. Squishing them or washing them off with water makes them sting more (NCCEH).
• Need help? Get a quote from a recommended local exterminator through Pest Agent's referral form.

Knowing how to get rid of red ants starts with an odd fact: the ones that swarm and sting in a Canadian yard usually come from nests you cannot see. European fire ants usually build no mound, so the large ant hill by the patio likely belongs to another species, while the colony stinging your ankles often sits under a stone, a log or a damp garden bed.

Red ants in the kitchen are a different insect with a different fix, and a spray aimed at one can scatter the other into new nests. Colour alone does not settle which ant you are dealing with, since several Canadian ants can have that reddish tone.

What Are Red Ants and Fire Ants in Canada?

Red ants in Canada are most often European fire ants outdoors and small reddish house ants, such as pharaoh ants, indoors. Health Canada notes that ants can be black, brown, red or yellow, and most common Canadian ants are not aggressive. The red ant that causes real trouble in yards is the European fire ant, an invasive species that stings when you disturb its nest.

What Are Fire Ants?

Fire ants, in the Canadian sense, are usually European fire ants (Myrmica rubra). According to the National Collaborating Centre for Environmental Health (NCCEH), they are very small, reddish, aggressive ants that can bite and then sting a person or pet several times; Health Canada notes that most ants in Canada are not aggressive, although some can sting. They are related to the "true" fire ants that are a well-known problem in the southern United States, the red imported fire ants that build dome-shaped mounds up to about 1 foot (about 30 cm) high (UC IPM). The fire ant most Canadians run into is the European one, and it behaves differently: its nests are hidden in the soil and it builds no mound.

What Do European Fire Ants Look Like?

European fire ants are about 4 to 5 mm long and reddish-brown, sometimes with a darker head. Queens can reach up to about 9 mm (City of North Vancouver). Up close, they have a waist made of two segments, two small spines pointing backward on the middle of the body, and a stinger. You need a magnifying glass to see these details, and Metro Vancouver advises having an expert confirm the identification, because some native red ants also sting. The clearest clue is behaviour: invasive fire ants tend to swarm quickly and sting when disturbed (District of Saanich).

Where Are Fire Ants Found in Canada?

Fire ants have been detected in most provinces: according to the NCCEH, Saskatchewan and Manitoba had not reported infestations. They are established in Quebec, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and British Columbia, where they were first recorded around 2010 and have since spread across the Lower Mainland, the Fraser Valley and Vancouver Island. They like moist soil and shade: lawns, garden beds, tree roots, and the ground under rocks, logs, landscape stones and yard waste. Their nests leave little more than a small amount of loose soil, so most people find them by stepping on one.

Which Red Ants Are Not Fire Ants?

Many red ants are not fire ants. Indoors, pharaoh ants are tiny (about 1.5 to 2 mm), yellow to reddish, and usually live in heated buildings, so see our guide to pharaoh ants if you find them in the kitchen or bathroom. Thief ants are even smaller and yellow to light brown, and our guide to small ants in the house covers them. Red carpenter ants are much bigger, 6 to 25 mm, with a reddish-brown upper body (how to get rid of carpenter ants). Outdoors, Metro Vancouver notes that large ant hills usually belong to other species, not European fire ants.

Do Red Ants Sting?

Most ants in Canada are not aggressive, Health Canada notes, but some can sting, and European fire ants do. When their nest is disturbed, they come out in numbers and sting people, pets and wildlife repeatedly, and the stings are painful and itchy (Metro Vancouver). In rare cases they cause serious allergic reactions, which is covered in the first aid section below.

How to Get Rid of Red Ants in Your House

Getting rid of red ants in your house starts with naming the ant. European fire ants usually form colonies outdoors (NCCEH), so red ants trailing across your counter are either fire ant foragers wandering in from the yard or, more often, small house ants. In both cases, slow-acting bait works better than spray, according to UC IPM.

Identify the Ant

Identifying the ant tells you where the colony is. Tiny yellow to reddish ants that show up all year, even in winter, point to pharaoh ants nesting inside the walls. Small red ants that sting and come in from a door near the lawn in summer point to fire ants nesting outside, which means the real treatment happens in the yard. If you are not sure, a magnifying glass and a photo for a pest professional or your local invasive species group will settle it.

Wipe the Scent Trail

Wiping the scent trail stops more ants from following it. UC IPM recommends cleaning invading ants up with soapy water, which removes the scent they leave for each other. Then clean up the crumbs, spills and pet food that drew them in.

Use Slow-Acting Bait

Slow-acting bait is often the most reliable way to get rid of red ants indoors. Workers carry it back to the nest and share it with the queens, so the colony dies, not just the ants you see. Health Canada recommends placing bait stations right in the path of foraging ants, out of reach of children and pets, and leaving them out for at least two weeks. Check that the label shows a PCP number, which means Health Canada has approved the product. In Canada, household boric acid ant products have been sold only as sealed bait stations or gels since July 22, 2018, and Health Canada advises against making your own boric acid pesticides. For product picks, see our best ant killer guide and our guide to boric acid for ants.

Avoid Sprays While Baiting

Sprays undo the work of baits. Health Canada warns that spraying ants while you use a bait system will stop the bait from working, and with pharaoh ants, sprays and repellents can make the colony split into new nests (Alberta Health). Let the ants feed, even if you see more of them around the bait for a few days.

Seal Entry Points

Sealing entry points keeps the next wave out once the colony is gone. Health Canada suggests caulking cracks along baseboards and in the foundation and fixing leaks. For the full step-by-step method that works on most species, read our guide on how to get rid of ants.

How to Get Rid of Fire Ants in Your Yard

Getting rid of fire ants in a Canadian yard means finding the hidden nests, treating them with products registered in Canada, and following up. It is hard work: each colony can have many queens and spread over several nests (Metro Vancouver). Metro Vancouver states that insecticide use is currently the only effective control method for European fire ants in British Columbia.

Protective Clothing

Protective clothing comes first, because finding and treating nests means disturbing them. Metro Vancouver recommends gloves, closed-toed shoes or boots, and pants tucked into your socks, with no exposed skin where ants can get in; Penn State Extension gives similar advice for treating stinging insect nests.

Finding Fire Ant Nests

Finding fire ant nests is easiest with apple slices. European fire ants often forage within a metre or so of their nests and crowd onto apple slices near a nest. Metro Vancouver's method:

1. Lay out apple slices about 1 metre apart in a rough grid over the problem area.
2. Check the slices within about an hour.
3. Where fire ants cover a slice, a nest is likely nearby, often within a few metres.
4. With protective clothing on, tap the ground around that slice and watch where the ants swarm out: that is the nest entrance.

Do this on a dry day when the ants are actively foraging.

Boric Acid Sugar Baits

Boric acid sugar baits can reduce fire ant numbers, but they will not wipe out a colony. Metro Vancouver recommends store-bought baits with 2% boric acid in a sugar solution and says to avoid baits with 4 to 5% boric acid, which are not effective. Place them around the nests in early to mid-summer, when the queens and young are eating the most, and replace them every week because they dry out in heat and get soaked by rain. Keep baits around the edges of vegetable gardens and raised beds, not inside them. Baits mostly kill workers rather than queens, so treat them as a way to slow fire ants down and stop their spread.

Nest Treatment With Insecticide

Nest treatment with an insecticide is the method Metro Vancouver lists for small to medium infestations: the soil is dug open to expose the nest while permethrin is applied, and Health Canada notes this may eliminate colonies. This is not a casual job. Permethrin is toxic to fish, pollinating insects, wildlife and pets, its use is restricted near water (UC IPM cites water quality concerns), and some provinces and municipalities restrict lawn and garden pesticides (Health Canada). Use only a product registered in Canada (look for the PCP number), follow the label exactly, keep children and pets away, and check your local rules first. If you would rather avoid insecticides in your garden, see our guide to plant-safe ant killers.

Does Boiling Water Work?

Boiling water only gives a short break. Health Canada says pouring boiling water and detergent down a nest temporarily reduces an ant colony's population, but fire ant colonies have many queens and many connected nests, so the effect does not last. For mound-building ants, our guide on getting rid of ant hills goes further.

Follow-Up Monitoring

Follow-up monitoring is part of any fire ant plan. Metro Vancouver advises checking treated sites regularly and treating again where ants are still active. Repeating the apple slice test later in the season shows whether any nests remain.

When to Call a Pest Control Professional

Calling a pest control professional makes sense when nests cover a large part of your yard, sit near water or a play area, or keep coming back after you treat them. The Invasive Species Council of BC advises against removing a nest yourself, and Metro Vancouver notes that nest treatment may require a professional. A licensed professional will typically inspect to find the nests and entry points, then use baits, targeted nest treatments and follow-up visits. To learn more, read about the cost of ant extermination in Canada or get a quote from a recommended local exterminator through Pest Agent's referral form.

Reporting Fire Ants in BC

Reporting fire ants in British Columbia helps track their spread. You can report a suspected find to the Invasive Species Council of BC at 1-888-933-3722 or through the Report Invasives BC app. Elsewhere, contact your municipality for local advice.

How Do You Prevent Red Ants From Coming Back?

Preventing red ants comes down to not carrying fire ants in on soil and plants, and making your yard and kitchen less inviting. European fire ants in BC generally do not produce flying queens, so they spread mostly by walking or by people moving soil and plants (Invasive Species Council of BC).

Garden Material

Garden material is the main way fire ants reach new yards. The City of North Vancouver identifies infested potted plants, soil and mulch as a main route of spread. Check landscaping supplies for ants before you bring them home and return them if you find any. If you have fire ants, do not move soil, turf, mulch, plants or leaf litter off your property.

Reduce Moisture

Reducing moisture makes your yard less attractive to fire ants, which prefer damp, warm ground. The City of North Vancouver recommends reducing watering in areas where fire ants are a problem.

Clear Yard Clutter

Clearing yard clutter removes the spots where nests settle. Paving stones, wood on the ground, lawn ornaments and other clutter trap heat and moisture (City of North Vancouver). Metro Vancouver notes that removing rocks, logs and debris can lower fire ant numbers, although it will not get rid of them on its own.

Food Storage Indoors

Food storage indoors keeps house ants from setting up trails. Health Canada recommends keeping food in sealed containers, keeping counters clean and emptying the kitchen garbage often.

What Should You Do If Fire Ants Sting You?

Fire ant stings can burn for about 30 minutes to two hours, then itch for a few days to a week (City of North Vancouver), and most need only simple first aid. Step away from the nest first so you are not stung again.

Get the Ants Off

Getting the ants off quickly limits the number of stings. The NCCEH recommends brushing them off with fast hand movements, and warns that squishing them or trying to wash them off with water makes them sting more.

Wash the Sting

Once the ants are off, wash the stings with clean water and put an ice pack wrapped in a cloth on them for 15 to 20 minutes at a time (HealthLinkBC).

Cool the Sting

Cooling the sting with a cold compress eases the swelling and pain.

Leave Pustules Alone

Leaving pustules alone lowers the risk of infection. If blisters or pustules break, they can become infected, so do not scratch or pop them, and see a doctor if the pain lasts or the area looks infected.

Signs of an Allergic Reaction

Signs of an allergic reaction need fast action. Get emergency help right away for swelling of the face, eyes or throat, trouble breathing, hives over the body or feeling faint, because a severe (anaphylactic) reaction can be life-threatening. These reactions are rare, but the NCCEH notes they can appear hours after the sting. For a reaction stronger than minor swelling, redness and itching, call your provincial health line (8-1-1 in British Columbia) for advice.