How to Choose a Contractor in Ontario: Red Flags to Watch For

This is non-negotiable. Any legitimate contractor working in Ontario must carry general liability insurance and must be registered with the Workplace Safety and Insurance Board (WSIB). If a worker is injured on your property and the contractor doesn't have proper WSIB coverage, you can be held financially responsible. Ask for a Certificate of Insurance and a WSIB Clearance Certificate — both current, both specific to your project. If they hesitate or make excuses, stop the conversation.

A reasonable deposit is 10–15% of the project value at contract signing, sometimes with an additional materials deposit at construction start. Any contractor requesting 30%, 40%, or 50% before work begins is a significant warning sign. Contractor fraud in Ontario most commonly involves collecting large deposits and disappearing, or starting work and abandoning the project once they have enough of your money. Tie payments to milestones, not to calendar dates.

High-pressure urgency tactics — "I have a crew available right now but they're booked next week" or "this price expires at the end of the day" — are classic pressure-selling techniques. A reputable contractor with consistent work has no reason to rush you into a decision. If they're creating artificial urgency, ask yourself why they're that eager to close you before you can do due diligence.

Unpermitted work is your problem, not theirs. When you sell your home, a buyer's inspector or lender will often discover unpermitted structural or mechanical work — which can kill a sale, require remediation, or reduce your home's value. Unpermitted work can also void your homeowner's insurance policy if a claim arises from that area. Any contractor who frames permit avoidance as a favour to you is either cutting corners, hiding something about their registration status, or both.

If you get three quotes and one is 40% lower than the other two, it's not a deal. It's a gap in scope, an underqualified crew, substandard materials, or a contractor who will make up the difference in change orders once they're on site. Competitive pricing exists, but gravity applies to construction: you get what you pay for. Understand why a quote is low before treating it as an advantage.

Ask for three to five references from projects completed in the last two years, similar in scope to yours. Then actually call them. Ask specific questions: Did the project finish on schedule? Were there unexpected costs? How was communication when problems arose? Would you hire them again without hesitation? Scripted or vague references, or a contractor who can only provide one reference, are red flags. Strong contractors have a deep bench of willing past clients.

In Ontario, any home renovation contract over $50 must be in writing under the Consumer Protection Act. But the legal minimum isn't enough — a proper contract specifies scope line by line, materials and specifications, a payment schedule tied to milestones, a timeline with start and substantial completion dates, a change order process, and dispute resolution language. A one-page agreement with a total price and a start date is not a contract that protects you.

A contractor without Google reviews, a website, or any verifiable track record is a contractor without accountability. This doesn't mean a newer company is automatically suspect — but it does mean you have less to verify. Cross-reference their business name, registration, and physical address. Ask how long they've been operating and ask to see evidence of past work. Established contractors have digital footprints.