Guide
When to Call an Exterminator in Ottawa
Last reviewed October 2026.
Signs you need professional pest control
On this page
You find droppings, gnawed wires, or nests. You hear scratching in walls or ceiling voids. DIY traps and sprays keep failing. These signs often mean the pest problem is beyond what over-the-counter products can handle. A licensed professional can identify the source and apply the right treatment.
When pests are most active in Ottawa
As Ottawa cools, mice and rats move toward heated buildings. Average temperatures drop from 15.6 °C in September to 8.8 °C in October and 2.0 °C in November. This seasonal shift pushes rodents indoors, making fall a common time for infestations to start or become noticeable.
What pest control costs in Ottawa
Based on published prices from three Ottawa companies, read October 21, 2026, a one-visit mouse treatment starts at about $250. Final cost depends on the pest type, property size, and how many follow-up visits are needed. Always get a written quote that spells out what is applied and the number of visits included.
Questions to ask before hiring
- Does the technician hold a valid Ontario pesticide exterminator licence (structural class for buildings)? Does the business carry the required operator licence and insurance?
- What product will be applied, and is it safe for children and pets?
- How many follow-up visits are included, and what is the guarantee?
- Will the company check that basement openings, floor drains and ventilation openings are screened to keep vermin out, as required under Ottawa’s Property Standards By-law?
Ottawa pest control licences and the property standards by-law
In Ontario, a person applying pesticides commercially on property they do not own must hold a pesticide exterminator licence. The structural class covers buildings. The business itself needs a separate operator licence and must carry insurance for its pesticide operations. Ottawa’s Property Standards By-law requires that a dwelling be kept free of vermin. Basement openings, floor drains and ventilation openings must be screened with material that keeps vermin out.
How long does pest control take?
A single wasp nest can often be removed in one visit. Mice and carpenter ant treatments typically take a few weeks, with multiple visits needed to fully eliminate the infestation. A reputable company will explain the expected timeline before work begins.
How to choose a pest control company in Ottawa
Compare at least three companies. Check dated Google ratings and the number of reviews. Look for clear pricing, licence numbers on their website, and a willingness to answer the questions above. If you sign a contract in your home, Ontario law gives you a 10-day cooling-off period after you receive the written contract. Avoid any company that pressures you or refuses to provide a written quote.
Need a list of local pros? See our guide to pest control companies in Ottawa, complete with ratings, costs, and a free quote request form.