Certificate of completion (Ontario Construction Act)

In Ontario's Construction Act, a certificate of substantial performance certifies the head contract (section 32) and must be published to take effect, while a certificate of completion certifies that a subcontract is finished (section 33) — and each certificate is what starts the clock on releasing the 10% statutory holdback.

The two certificates

Ontario's Construction Act, R.S.O. 1990, c. C.30 runs on two certification events. The certificate of substantial performance is the head-contract milestone: under section 2(1), a contract is substantially performed when the improvement — or a substantial part of it — is ready for use or being used for the purposes intended and capable of completion at a cost not exceeding 3% of the contract price (1% for contracts with a delayed-occupancy term in the sale of a new home). Under section 32, the payment certifier (or the owner and contractor jointly, where there is no certifier) signs the certificate in the prescribed form, sets out the date of substantial performance, gives copies within seven days, and the contractor must publish it as the regulations require. Under section 32(10), a certificate of substantial performance has no effect until published.

A certificate of completion is different: under section 33, at the contractor's request the payment certifier can determine that a subcontract has been completed and certify that completion in the prescribed form (or the owner and contractor can jointly declare it). The subcontract is deemed completed on the certification date, and copies go to the subcontractor within seven days. It is a subcontract-level document — not the end of the head contract.

What each certificate does to the holdback

Part IV of the Act requires a 10% holdback (section 1(1) and section 22). Certificates govern when that money moves: under section 25, once a subcontract is certified complete under section 33 and its liens have expired or been provided for, payers can safely release the holdback they retained for that subcontract. For the head contract, section 26 (as rewritten by the 2024 amendments, in force January 1, 2026) requires payment of accrued basic holdback following each annual anniversary — the owner publishes a notice of annual release within 14 days of the anniversary and must pay at least 60 but no later than 74 days after that notice — with holdback not otherwise paid released within 14 days after all potential lien claims against it expire or are satisfied. Section 27 discharges the separate holdback kept on finishing work supplied after substantial performance (section 22(2)).

Why the dates matter

The published date of substantial performance starts several clocks at once: it fixes the date from which liens on the contract must be preserved and perfected (Part V), triggers the finishing-work holdback, and anchors the basic-holdback release mechanics. A certificate with the wrong date, or a certificate that never gets published, is a recurring source of disputes — which is why section 32(7) lets a court declare substantial performance where the certifier fails or refuses to certify within a reasonable time.

What it means for vendors

Subcontractors: request certification of completion under section 33 when your scope is done — it's the mechanism that unlocks your holdback downstream. Contractors: publish the certificate of substantial performance promptly (any person may publish it under section 32(6) if you don't), and track the annual-holdback calendar the 2024 amendments introduced. Owners and payers: verify liens have expired or been satisfied before releasing, and use the prescribed forms.

Common questions

Is "certificate of completion" the same as "certificate of substantial performance"?

No. Substantial performance certifies the head contract under section 32 and must be published to take effect; a certificate of completion under section 33 certifies that a subcontract is finished and doesn't depend on publication.

Does a certificate of completion release the owner's holdback to the contractor?

It lets payers reduce the holdbacks they retain to the extent of the completed subcontract (section 25). The owner's basic holdback moves under section 26 — now on an annual-release schedule — once lien claims are expired or provided for.

Related definitions

Substantial performance · Retainage vs. holdback · Progress payment