Montreal and surrounding area
Mouse extermination in Montreal
Noises in the walls at night, droppings behind the appliances? We eliminate the mice present, find where they get in and seal those entry points — otherwise they come back.
- CD5-certified technicians
- Entry points sealed
- Written guarantee
- Montreal and surrounding area
Residential and commercial · Montreal, Laval, South Shore and North Shore
Suspect mice in your home?
What we most often find when inspecting a house or apartment:
- Scratching noises in the walls or ceiling, especially at night
- Small black rice-shaped droppings near appliances
- Chewed packaging, bags or boxes in the pantry
- A persistent urine smell in a cupboard or basement
- Greasy rub marks along baseboards and walls
- Shredded paper, cardboard or insulation used as nesting material
A mouse fits through an opening the size of a dime. As long as those openings stay open, eliminating the ones already inside solves only half the problem.
How our intervention works
Eliminate, then keep them out: the two halves of the job.
Inspection
We follow the traces to the runways and nests, inside and around the building, and note every opening a mouse can get through.
Elimination
Devices chosen according to the premises and the presence of children or pets, placed along the runways actually in use — not at random in the middle of a room.
Sealing the entry points
This is the step most people skip, and the number one reason mice come back: the openings found during the inspection are blocked with materials rodents can't chew through.
Follow-up and guarantee
We check residual activity and adjust if needed. The treatment is covered by a written guarantee, handed over at the end of the intervention.
Limited offer · Only 6 days left
10% off bed bugs, cockroaches and rodents treatments
Valid for any intervention booked by August 31, 2026. Mention code AOUT10 when you call.
Free on-site inspection and quote, written guarantee: always included, offer or not.
What our clients say
Reviews published on our Google profile.
« Quick and very professional service. The team explained the problem and solution clearly. Impeccable result, highly recommend! »
« Honestly amazing service. They responded quickly, arrived on time, and explained everything without stressing me out. »
« Thanks for your help. My home is finally clean again. Fast, professional service and excellent customer care. »
WHY CHOOSE US
Why choose 514 Extermination for your mice?
Catching mice and solving a mouse infestation are two different things. As long as the openings they come in through stay open, you're just emptying a room that keeps refilling.
We seal, not just trap
Smoke testing to reveal openings the eye can't see, then professional sealing with materials rodents can't chew through. That's the step that stops them from coming back.
With or without poison: you choose
Mechanical traps with no toxic product, or locked bait stations depending on your situation. The poison-free option suits families with children and pets, kitchens and restaurants.
We look for how they get in
A mouse fits through an opening the size of a dime. We inspect around the foundation, pipe entries, vents and thresholds — not only where you saw droppings.
Thought-out placement, not random
Devices go along the runways actually in use, revealed by the traces. A trap in the middle of a room is useless: a mouse follows the walls.
CD5-certified technicians
Holders of the CD5 certificate, Health Canada approved products dosed by a professional, placed out of reach of children and pets.
Free inspection, written guarantee
We assess the situation at no cost and with no obligation, and you decide afterward. The treatment is covered by a written guarantee handed over at the end.
Prefer to handle it by phone?
Call (514) 835-2108Frequently asked questions
Aren't store-bought traps enough?
Why do mice come back every fall?
How long before it's resolved?
Is it safe for children and pets?
What if a mouse dies inside a wall?
Do you treat apartments and rental buildings?
How much does mouse treatment cost?
Learn more about mice
The house mouse: small but invasive
The house mouse (Mus musculus) is the most common rodent in Quebec homes. Quick, curious and extremely prolific, it lives in organized groups and adapts to almost any environment. Its small size makes it formidable: it can squeeze through a hole the size of a dime (about 6 mm).
A seemingly harmless presence — "just one mouse" — often hides a forming colony. Without intervention, the problem escalates quickly.
Explosive reproduction
- A female can have 4 to 8 litters per year.
- Each litter has 6 to 12 pups.
- Weaning happens at just 5 weeks — young already breed within weeks of life.
- Lifespan: 2 to 3 years.
In short: if you see one mouse, there are probably several more hidden in the walls. That's why acting early is essential.
How do they get in?
Mice seek warmth, food and shelter, especially at the first fall cold snaps. They enter through:
- Foundation cracks and brick joints
- Poorly sealed pipe, wire and duct passages
- The bottom of garage doors and thresholds
- Dryer and ventilation ducts
- Utility entry points (water, electricity)
Quebec's climate drives mice indoors from fall onward — the highest-risk period.
Health risks
Mice aren't just a nuisance: they contaminate food and surfaces with their droppings, urine and saliva. They can transmit salmonellosis, leptospirosis and other pathogens. In Quebec, the deer mouse (in rural areas and cottages) can transmit hantavirus, a serious virus. Important: never dry-sweep or vacuum mouse droppings — first dampen with disinfectant to avoid suspending particles.
For more, see our articles on diseases transmitted by mice and hantavirus and rodents.
Property damage and fire risk
Mouse teeth grow continuously: they must gnaw constantly to wear them down. As a result, they attack insulation, wood, packaging — and especially electrical wires. Chewed sheathing exposes conductors and creates a real fire risk. A significant share of residential fires of undetermined cause is estimated to be linked to rodents damaging wiring.
Signs of an infestation
- Small black droppings (3-6 mm) along walls, under the sink, in cabinets
- Scratching noises at night in walls or ceiling
- Gnawed food packaging
- Persistent musky odor
- Grease marks along baseboards (regular trails)
- Nests of shredded paper, fabric or insulation
How to prevent an infestation
A few habits sharply reduce the risk, especially before fall:
- Seal entry points: cracks, pipe joints, garage door bottoms, dryer ducts.
- Store food (including pet kibble) in airtight containers.
- Take out the trash regularly and keep lids closed.
- Reduce moisture and fix leaks — water attracts rodents.
- Keep firewood and debris away from foundations.
Prevention doesn't replace treatment once an infestation is established, but it prevents recurrence after our intervention.
Go further
Prepare before the intervention
What to clear and store so the technician can work effectively.
After the treatment
What's normal to see, and when to call us back.
Mouse or rat?
Size, droppings and traces: how to tell them apart.
All our rodent services
Mice, rats and full building exclusion.
Mouse extermination by area
Mice to get out of your home?
Call us: we assess the situation, find the entry points and tell you what needs to happen, no obligation.