A lien claim isn't a form filled out on the deadline day. It's a package assembled as the job runs, because the deadline to preserve it arrives long before most people start looking for the paperwork.
Key takeaways
The paperwork that actually preserves a lien is smaller than most people expect — a statement of lien in the prescribed form, supported by the documents that prove the amount and the date. What takes time isn't the form itself; it's tracking down the last-supply date, the certificate that started the clock, and a lien amount that's been recomputed rather than estimated, all while the deadline is already running.
Ontario's Construction Act runs a two-stage clock: a lien must be preserved within 60 days, with the trigger depending on your position in the chain and the project — publication of a certificate of substantial performance, completion, abandonment or termination of the contract, or your own last supply of services or materials. Once preserved, it must then be perfected within 90 more days, meaning an action is commenced and a certificate of action registered on title (or the equivalent step where the lien attaches to holdback rather than land). The distinction between the two steps is exactly where a package assembled too casually falls apart — preserving without perfecting still loses the lien once the second window closes.
Worked example: Ontario's clock, run from a supplier's last delivery
A material supplier's last delivery to the job is March 2, 2026. Sixty days from that date — the preserve deadline — is May 1, 2026.
Assuming the lien is preserved on time, the perfect deadline runs ninety more days from that preserve date, not from the original last-supply date: July 30, 2026 is the outside limit to commence the action and register the certificate of action.
Both dates are counted from the trigger that actually applies to that claimant's position in the chain — a general contractor's own trigger may run from a different event than a material supplier's. Confirm which trigger applies before counting the days, not after.
Assembled early, the package should hold: a copy of the contract or subcontract establishing the claimant's relationship to the job, the date of last supply of services or materials (or the publication date of the relevant certificate, whichever trigger applies), the invoices and correspondence proving the amount claimed, and a computed lien amount that's been recalculated from the job's own numbers rather than carried forward from an old estimate. Material suppliers, not only contractors, can register a lien when unpaid, so the same package discipline applies whether the claimant is at the top of the chain or several tiers down. Note too that missing the deadlines does not end the right to sue for the money owed — the contract claim survives — it only loses the lien's security against the property.
British Columbia's Builders Lien Act follows its own timeline. Under section 20, a claim of lien may be filed no later than 45 days after a certificate of completion is issued, or after the head contract or the improvement is completed, abandoned or terminated. That is a single deadline, not Ontario's two-stage preserve-then-perfect structure — do not apply Ontario's 60/90 count to a BC job. Section 34(2) also specifies exactly what a BC statement of lien must contain, so the package for a BC claim should be built directly against that statutory checklist rather than assumed from an Ontario template.
BC's clock, on the same facts
A certificate of completion is issued on April 10, 2026. The 45-day filing deadline under s. 20 runs to May 25, 2026.
Separately, s. 8(1) sets the holdback period itself to expire 55 days after that same certificate — June 4, 2026 on these facts — which is a different date serving a different purpose from the lien-filing deadline, even though both run from the same certificate.
Under s. 17, a lien claim under $200.00 cannot be filed at all — a minimum threshold Ontario's Construction Act does not carry.
Not every improvement gets registered against title. On Crown land, municipal projects and certain public premises, a claimant does not register against title — instead, written notice of the lien goes to the right party, and the lien attaches to the holdback rather than the land itself. The package for that kind of claim needs the same underlying documents — contract, last-supply date, computed amount — but the delivery mechanism is different, and confirming who the notice actually has to go to matters as much as confirming the deadline. A claimant who assumes every project runs the same registration process risks delivering the right package to the wrong place.
The single most useful comparison in this area is that Ontario and BC both use a 10% holdback, but almost nothing else lines up: BC's holdback period runs 55 days from a certificate of completion and its filing window is 45 days, against Ontario's 60-days-to-preserve then 90-more-to-perfect. A package built for one province's clock, reused on a job in the other, is a package built around the wrong deadline. If the claim ever needs to fall back to a bond claim instead of a lien claim, that decision should be made early too — the two routes run on entirely different clocks.
It depends on the claimant's position in the chain: publication of a certificate of substantial performance, completion, abandonment or termination of the contract, or the claimant's own last supply of services or materials — confirm which trigger applies before counting days.
The security against the property is lost, but the underlying contract claim for the money owed survives — it can still be pursued as a debt claim, just without the lien's priority against title.
No. BC's Builders Lien Act runs a single 45-day filing deadline from the certificate of completion, a materially different structure from Ontario's two-stage preserve-and-perfect clock. Treat the two as entirely separate regimes.
In British Columbia, yes — s. 17 of the Builders Lien Act bars a claim under $200.00. Ontario's Construction Act does not carry an equivalent statutory minimum.
Rather than registering against title, written notice of the lien is delivered to the appropriate party and the lien attaches to the holdback instead. The underlying supporting documents are the same; confirm who the notice must be delivered to before the deadline arrives.
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