Ask the contractor for their licence or certification number, then check it: plumbers and most compulsory trades on the Skilled Trades Ontario Public Register, and electrical contractors in the Electrical Safety Authority database.
Here's the part that surprises most homeowners: there is no single "general contractor" license in Ontario. Licensing is split across different trades and different regulatory bodies, so "are they licensed" actually depends on what work they're doing. Here's how to check it properly, trade by trade.
The two places you'll actually need to check
Depending on the trade, verification happens through one of two official registries:
- Skilled Trades Ontario (STO) Public Register — covers most compulsory trades, including plumbers (306A certification). Skilled Trades Ontario replaced the old Ontario College of Trades in January 2022, so if a contractor points you to "the College of Trades," that's outdated — the current registry is Skilled Trades Ontario's.
- Electrical Safety Authority (ESA) database — electrical work is regulated separately, through the Electrical Contractor Registration Agency (ECRA/ESA). Search by company name or licence number directly at their site.
What "compulsory trade" actually means
Ontario has 23 compulsory trades — electricians and plumbers among them — where the person doing the work must hold a valid Certificate of Qualification, or be a registered apprentice working under someone who does. For these trades, working without certification isn't a grey area — it's not legally permitted.
For non-compulsory trades, verification still exists, just differently — you can email verification@skilledtradesontario.ca directly, though it typically takes about 10 business days to hear back.
The one question that catches most problems
You don't need to memorize registry websites to protect yourself. Simply ask directly for the licence or certification number, and check it while they're still standing in front of you if you can. A legitimate, licensed contractor will give you this without hesitation — it's public information they're required to have anyway. Hesitation, deflection, or "you don't need to worry about that" is the clearest warning sign there is.
Quick answers
Is there a general contractor licence in Ontario?
No, Ontario has no single general contractor licence. Licensing is split by trade and regulator, so what counts as licensed depends on the work being done.
How do I check if a plumber is licensed in Ontario?
Search the Skilled Trades Ontario Public Register, which covers plumbers with 306A certification. Skilled Trades Ontario replaced the old Ontario College of Trades in January 2022.
How do I check if an electrician is licensed in Ontario?
Search the Electrical Safety Authority database by company name or licence number. Electrical work is regulated separately, through the Electrical Contractor Registration Agency.
What is a compulsory trade in Ontario?
It's one of 23 trades, including electricians and plumbers, where the worker must hold a valid Certificate of Qualification or be a registered apprentice under someone who does. Working uncertified in these trades isn't legally permitted.
How can I verify a contractor in a non-compulsory trade?
Email Skilled Trades Ontario at verification@skilledtradesontario.ca. It typically takes about 10 business days to hear back.
Five minutes, before you sign anything
Licensing rules in Ontario are genuinely fragmented, and that's not your fault for finding it confusing — it trips up experienced homeowners too. The good news: it only takes one direct question and a two-minute registry search to actually confirm it, rather than just trusting a truck logo or a business card.
Related reading
- How Do Building Permits Actually Work in York Region?
- How Rhodex Vets a Craftsman Before They Reach Your Door
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