Boxelder bugs cluster on sun-warmed exterior walls in fall, looking for cracks and gaps to overwinter in, then reappear indoors on warm winter days once they’ve made it inside wall voids or attics.
They don’t bite or cause structural damage, but large clusters are unpleasant indoors and can stain fabric and surfaces if crushed.
We apply perimeter treatment before the fall migration begins where possible, and seal the cracks and gaps around windows, siding, and soffits that boxelder bugs use to get inside.
Full service area: Ajax · Aurora · Bradford · Brampton · Bowmanville · Clarington · Courtice · Durham · East Gwillimbury · East York · Etobicoke · Georgina · Keswick · King City · Maple · Markham · Mississauga · Mount Albert · Newcastle · Newmarket · Nobleton · North York · Oshawa · Pickering · Port Perry · Richmond Hill · Scarborough · Scugog · Stouffville · Thornhill · Toronto · Toronto Beaches · Uxbridge · Vaughan · Whitby · Woodbridge · York Region
No, they're harmless to people and structures — the main issue is large numbers gathering on sunny walls and occasionally getting indoors.
They're searching for a sheltered spot to overwinter as temperatures drop, which is when large clusters form on exterior walls.
It's a fine short-term fix indoors, but sealing entry points and perimeter treatment before fall reduces next year's numbers.
Quality Pest Control GTA service will eliminate your pest and wildlife problems within your home, business, or property in Durham and York Region.
Quality Pest Control GTA © 2026. All Rights Reserved.
