How the deadlines work
Ontario's prompt payment rules are in Part I.1 of the Construction Act, R.S.O. 1990, c. C.30. They have applied since October 1, 2019, and the version this calculator follows includes the amendments in force on January 1, 2026. For the full picture, including lien deadlines and adjudication, read our guide to Ontario holdbacks, prompt payment and lien deadlines.
Owner to contractor: 14 and 28 days after receipt
The owner must pay a proper invoice no later than 28 days after receiving it (section 6.4 (1)). To withhold any part, the owner has to give a notice of non-payment in the prescribed form (Form 1.1) no later than 14 days after receiving the invoice, stating the amount and all of the reasons (section 6.4 (2)). Anything not covered by the notice is still due on day 28 (section 6.4 (3)), less the 10% holdback (section 6.2).
Since January 1, 2026, an invoice that is missing required information is deemed to be a proper invoice unless the owner tells the contractor in writing, within 7 days after receiving it, what is deficient and what is needed to fix it (section 6.1 (2)). Proper invoices go out monthly unless the contract says otherwise (section 6.3 (1)), and a contract cannot make giving one conditional on prior certification or the owner's approval (section 6.3 (2)).
Contractor to subcontractor: 7 days after payment, 35 days at the latest
A contractor paid by the owner must pay each subcontractor whose work was in the invoice no later than 7 days after receiving payment (section 6.5 (1)). If the owner paid only part, the contractor pays out of what it received, rateably (section 6.5 (2) and (3)).
If the owner does not pay, the contractor must still pay its subcontractors no later than 35 days after giving the proper invoice to the owner (section 6.5 (4)), unless by then it gives them a notice of non-payment. A notice blaming the owner's non-payment must include a copy of any owner notice and an undertaking to refer the matter to adjudication no later than 21 days after giving it (section 6.5 (5)). If the owner did give a notice, the contractor's own notices are due within 7 days after receiving it (section 6.5 (7)).
Further down the chain: 7 days, 42 days at the latest
A subcontractor paying its own subcontractors follows the same pattern: 7 days after it is paid (section 6.6 (1) and (2)), and if the contractor pays it nothing, no later than 42 days after the proper invoice was given to the owner, unless it gives a notice of non-payment (section 6.6 (4) to (8)). A subcontractor can ask the contractor to confirm the date it gave the invoice to the owner (section 6.6 (10)). Late amounts carry interest at the prejudgment rate or the contract rate, whichever is higher (section 6.9).
Holdback and the annual release
Every payer retains a holdback of 10% of the price of the services or materials as actually supplied (section 22 (1)). Since January 1, 2026, the owner must publish a notice of annual release of holdback (Form 6, on a construction trade news website) no later than 14 days after each anniversary of the contract, then pay the year's accrued holdback at least 60 and no later than 74 days after publishing it (section 26 (2) to (4)). Contractors pay subcontractors within 14 days after receiving it (section 26 (5)). Preserved or perfected liens pause the release (section 26 (4)). For contracts entered into before 2026, the first release comes on the second contract anniversary after January 1, 2026 and includes everything accrued before it (section 87.4 (4)).
How holidays move a deadline
The Construction Act does not define its own holidays, so Ontario's Legislation Act, 2006 applies. The day of receipt is not counted (section 89 (5)), so day 28 is 28 calendar days later. A time limit that would expire on a holiday is extended to the next day that is not a holiday (section 89 (1)). Holidays are defined in section 88: every Sunday plus the days below. Saturday is not a holiday, so a deadline on a Saturday does not move. The August Civic Holiday and the National Day for Truth and Reconciliation are not on the list, and neither is the day after Remembrance Day when November 11 is a weekend.