Pest Control in Markham

Markham runs from the heritage Main Streets of Unionville and Markham Village to the condo towers going up at Markham Centre by Highway 7, and each of those pockets brings its own pest. Two Markham jobs have their own pages: mice and rat control in Markham and cockroach control in Markham. Carpenter ants work the mature treed lots, mice pour into the subdivisions every fall, and German cockroaches ride into the older apartment stock and the busy Highway 7 restaurant strip. We are a GTA company, not a national franchise, and our exterminators treat homes and businesses across all of Markham with same-day and 24/7 service, a free inspection, and a two-month guarantee. If a Markham home or unit is on the phone with a problem, we can usually be there today.

(888) 885-3070

The homes of Markham, and the pests that come with them

Markham is really several housing eras stacked in one city, and the pest that calls you depends on which one you live in.

The heritage pockets, Unionville around historic Main Street and old Markham Village, are the affluent treed lots with big mature canopy and homes that have stood for decades. That mature tree cover is exactly what carpenter ants want. They nest in the moisture-softened wood of an old tree or a fence post outside and then push a satellite colony into a deck ledger, a window frame, or a wall void where a bit of water has gotten in. Thornhill on the west side is the same story: older, heavily treed, and prone to the same ant pressure. If you are seeing big black ants indoors in spring, or hearing a faint rustle in a wall, read the carpenter ant control page, because ants in a house that big are a wood-and-moisture problem, not a sugar-on-the-counter one.

The 1980s-through-2000s subdivisions, Milliken, Wismer, Berczy, Greensborough, are the classic York Region mouse ground. Every one of those homes has weep vents in the brick, a spot where the gas line enters, and a garage door sweep that has worn thin, and a house mouse only needs a gap the width of a pencil to get through it. When the overnight temperatures drop in fall, field mice leave the ravines and the remaining farm edges and look for a warm wall, and the subdivisions are the first buildings they hit. The mouse control page walks through why fall is the cheap time to call.

The newer builds, Cornell out by Markham Stouffville Hospital, Cathedraltown, Angus Glen, and Box Grove, are tighter and better sealed, but "newer" does not mean immune. New developments sit on ground that used to be field, so the first few autumns after a subdivision goes up the mouse pressure can actually be worse, because the mice were living right where the houses now stand.

Then there is Markham Centre, the new downtown rising by Highway 7 and Warden along the VivaNext rapidway. The condo towers there, and the older apartment stock in Thornhill and Milliken, are where we see German cockroach. This is a building-wide pest, not a housekeeping one: a roach moves through shared walls, plumbing risers, and stacked units, so one infested unit becomes a floor. If you are in a Markham condo or apartment and seeing them, the cockroach control page explains why the whole-unit approach matters.

The pests Markham calls about most

• Carpenter ants. The signature pest of treed Unionville, Markham Village, and Thornhill. Large black ants indoors, faint rustling in walls, and little piles of what looks like sawdust point to a nest in damp wood.
• Mice. Every fall, right across the subdivisions from Milliken to Greensborough to Cornell. Droppings behind the kitchen sink and scratching in the walls after dark are the tells.
• German cockroach. In the older Thornhill and Milliken apartment and condo stock, the Markham Centre towers, and the Highway 7 restaurant strip. A commercial kitchen problem as much as a residential one.
• Wasps and hornets. In the big backyards of the estate and heritage lots through summer, in soffits, sheds, and ground nests. See wasp nest removal.

The Markham neighbourhoods we cover

We work the whole city: Unionville, Markham Village, Thornhill, Milliken, Cornell, Berczy, Wismer, Greensborough, Cathedraltown, Angus Glen, Box Grove, and the Markham Centre condo corridor along Highway 7. Heritage home, 1990s subdivision, new build, or a condo unit high over Warden, we cover it, and we cover the commercial side too, the restaurants and food service along Highway 7 and the plazas that keep Canada's most diverse community fed.

Who is responsible: bylaw, health, and renters

Markham has a City of Markham property-standards bylaw, enforced by Markham by-law services, that requires a property to be kept free of rodents and pests. This is a City of Markham rule and York Region's own standard, not a Toronto one. Markham is part of York Region, so the health authority here is York Region Public Health, not Toronto Public Health, and there is no Toronto Rat Response Plan in play. Keep that straight, because the responsibilities and the phone numbers are different.

If you rent in Markham, the pest cost is almost always the landlord's. Under Ontario's Residential Tenancies Act, the landlord must keep the unit in a good state of repair and fit for habitation, and the Landlord and Tenant Board has held repeatedly that dealing with an infestation falls to the landlord. Your job as a tenant is to report it in writing and give reasonable access for treatment. A cockroach problem in a Thornhill or Markham Centre building is the landlord's to solve across the affected units, not something a single tenant should be paying out of pocket to chase.

How we work

We inspect for free, find the nest or the entry points rather than just the bugs you can see, and quote the job on the spot. We use Health Canada-registered products applied to label, and where rodenticide is involved it goes in tamper-resistant stations away from pets and children, per the PMRA rules. Every job carries a two-month guarantee: if the pest is still active inside two months, we come back once at no charge. The work is carried out by Insectica Pest Control, licensed and insured and BBB A-accredited, and we are available same-day and 24/7 across Markham.

Common questions

Reviewed August 2026.