Before a contractor starts work, you should have four things on file: a current certificate of insurance, a valid workers' compensation clearance (a WSIB clearance certificate in Ontario), proof of any licence their trade requires, and a signed agreement that sets out your requirements. Depending on the job, you may also need training records, service tags or permits. This guide explains what documents to collect from contractors, why each one matters, and what to check when it arrives.
The core documents to collect from every contractor
Whatever the trade, most hiring organizations start with the same short list. These documents answer the basic questions: is the contractor insured, are their workers covered, are they qualified, and have they agreed to your terms.
- Certificate of insurance (COI) showing commercial general liability, and auto liability if vehicles are used on site.
- Workers' compensation clearance, such as a WSIB clearance certificate in Ontario.
- Trade licences or certifications where the work requires them, for example an ESA Electrical Contractor Licence for electrical work.
- A signed contract or service agreement that states your insurance minimums, safety expectations and how documents will be renewed.
- Basic business details: legal name, operating name, address, a contact for compliance questions, and a business number.
Insurance: what to look for on the certificate
A certificate of insurance should show the insurer, the policy number, the coverage limits, and the effective and expiry dates. Many organizations ask for $2M per occurrence in commercial general liability as a typical minimum for commercial work, and $5M for higher-risk trades such as roofing, fire protection, demolition, restoration or elevator work. For more on setting limits, see how much liability insurance a contractor should carry.
- Your organization named as additional insured, if your contract requires it.
- A notice of cancellation clause, often 30 days.
- Professional liability for consultants and engineers, and pollution liability for environmental or abatement work.
- Names that match: the insured on the certificate should be the same legal entity you are contracting with.
Keep in mind that a certificate is evidence of coverage on the day it was issued. It does not guarantee the policy stays in force, which is why the expiry date matters as much as the limits.
Workers' compensation clearance
In Ontario, a WSIB clearance certificate confirms that a contractor is registered with WSIB and that their account is in good standing. While a valid clearance is in place, WSIB waives its right to hold you, as the principal, liable for the contractor's unpaid premiums and related amounts. Without one, you can be held liable for them.
Clearances are free, valid for up to 90 days, and most expire on February 20, May 20, August 20 and November 20. In construction, a clearance must be in place before work begins and for the whole duration of the work. You can verify a clearance online through WSIB, and you should keep clearance records for at least three years. Other provinces use their own documents, such as a WorkSafeBC clearance letter in British Columbia or an attestation de conformité from CNESST in Quebec.
Licences, training and job-specific records
Beyond insurance and clearance, the documents you need depend on the work. A few common examples in Ontario:
- Electrical work: an ESA Electrical Contractor Licence and a designated Master Electrician. Many jobs also require a notification or permit filed with ESA.
- Work at heights: Working at Heights training certificates from a CPO-approved provider for construction workers using fall protection. The training is valid for three years.
- Fire protection: proof that technicians are qualified for fire alarm testing under CAN/ULC-S536, and dated service tags on extinguishers after annual maintenance.
- Backflow testing: the tester's certification and the test report, as required by your municipality's bylaw.
What to watch out for
- Certificates that list a parent company or a different legal name than the one on your contract.
- Expiry dates that fall in the middle of a scheduled job.
- Subcontractors who arrive on site without their own documents. Many organizations require subs to provide the same set.
- Screenshots or emailed summaries in place of the actual certificate.
A document is only useful while it is current. Record the expiry date of every item you collect, not just the date you received it.
Keeping it current
Collecting documents once is the easy part. The ongoing work is noticing when they expire and asking for renewals before the next visit. Set a reminder 30 days before each expiry, ask for updated clearances each quarter, and store everything in one place per contractor. Our contractor compliance checklist can help you set your list, and Vendorpass can track these dates and request renewals from your vendors if you would rather not do it by hand.