Notice of Non-Payment in Ontario
Under the Construction Act, R.S.O. 1990, c. C.30
A notice of non-payment is the only way a payer can refuse, in whole or in part, to pay a proper invoice in Ontario without losing the dispute. It must be delivered within 14 days (Ont. Construction Act s. 6.4(2)) and must give the specific reasons for non-payment.
One of the forms carries a mandatory undertaking to refer the dispute to adjudication within 21 days (Ont. Construction Act s. 6.5(5)).
Ontario notice of non-payment deadlines
The statutory clocks for this topic in Ontario, with section citations.
| Clock | Value | Statute |
|---|---|---|
Notice of non-payment window Window to dispute an invoice. Miss it and the amount is generally payable in full. Ont. Construction Act Section 6.4 | 14 days | Ont. Construction Act Section 6.4 |
Undertaking to adjudicate When refusing to pass payment down, the payer must undertake to refer the dispute to adjudication within this window. Ont. Construction Act Section 6.5 | 21 days | Ont. Construction Act Section 6.5 |
The Ontario dispute window is 14 days
The notice-of-non-payment window in Ontario is shorter than the owner-payment window. A notice delivered after the 14-day window closes (Ont. Construction Act s. 6.4(2)) is generally treated as no notice at all, and the invoiced amount becomes payable in full.
The forms and the undertaking to adjudicate
Ontario follows the Ontario family of notice forms: one from an owner to a contractor, one from a contractor to a subcontractor when the owner has paid, and one when the owner has not.
When a contractor withholds payment from a subcontractor because the owner has not paid, the notice must include an undertaking to refer the dispute to adjudication within 21 days (Ont. Construction Act s. 6.5(5)). Tiercord branches to the correct form automatically and enforces that undertaking where it applies.
Reasons must be specific
A valid Ontario notice states the amount being withheld and the specific reasons for non-payment. Vague or boilerplate reasons can render the notice ineffective, so the wording matters as much as the timing.
Notice of non-payment in Ontario: FAQ
How long do I have to dispute an invoice in Ontario?
14 days from receipt of the proper invoice (Ont. Construction Act s. 6.4(2)). A late notice of non-payment generally means the full amount becomes payable.
Does a Ontario notice of non-payment require an undertaking to adjudicate?
When a contractor passes non-payment down to a subcontractor because the owner has not paid, yes: the notice must undertake to refer the dispute to adjudication within 21 days (Ont. Construction Act s. 6.5(5)).
See the full Ontario guide
Every deadline, notice and adjudication rule in one place.