Lien deadline calculator
Ontario's Construction Act gives you 60 days to preserve a lien and 90 days to perfect it, both counted from the date of substantial performance. Enter that date to get both deadlines.
- Preserve the lien by
- Register a claim for lien (Construction Act s.31)
- Perfect the lien by
- Start a court action and register a certificate of action (Construction Act s.36)
These calculators estimate statutory deadlines under Ontario's Construction Act. They adjust for weekends but not statutory holidays, and they're general information, not legal advice. Confirm exact timing with a construction lawyer before relying on a computed date.
Lien deadlines, explained
What's the difference between preserving and perfecting a lien?
Preserving a lien means registering a claim for lien (or, where there's no land interest, holding the claim in trust) within 60 days of the triggering date. Perfecting it means actually starting a court action and registering a certificate of action within 90 days of that same date. A preserved lien that's never perfected expires.
Is the 90-day perfection deadline counted from the preservation date?
No. Both the 60-day preservation deadline and the 90-day perfection deadline run from the same triggering date (here, substantial performance), not from each other.
What if the triggering date isn't substantial performance?
The same 60/90-day clocks also run from the date of contract completion or termination/abandonment, and from the date of last supply for a subcontractor's or supplier's lien, whichever applies to your claim. This calculator assumes substantial performance; use the applicable date for a different trigger.
See lien expiry tracked next to every other deadline.
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