Preserving and Perfecting a Construction Lien in Ontario: Deadlines You Cannot Miss

If you supplied labour, materials, or services to a construction project in Ontario and you have not been paid, you may have the right to register a construction lien against the property. That lien is a powerful remedy — it attaches a legal claim directly to the land itself, putting the owner, their lender, and every future buyer on notice that money is owed.

But a construction lien is not a set-and-forget protection. Ontario's Construction Act imposes a strict two-stage process: first you preserve the lien by registering it on title within a tight deadline, then you perfect it by starting a court action and setting the matter down for trial within a second deadline. Miss either stage and the lien is extinguished — not suspended, not curable, not fixable. Gone entirely, along with much of your leverage to collect.

This article walks through both stages, explains what each deadline means in plain language, and describes the consequences of letting either one slip.

Stage One: Preserving the Lien

What "preserving" means

To preserve a construction lien, you register a claim for lien in the land registry against the title of the property where the work was done. This is the act that officially puts the lien on the public record. Until you register, you have no lien — only an unsecured claim against the contractor or owner, which is far harder to enforce.

The preservation deadline — and how it is calculated

Under the Construction Act (as of writing — verify immediately with a lawyer), the deadline to preserve a lien is generally 60 days from the date of the event that triggers the limitation period. The trigger date depends on your role in the project:

• Contractors and subcontractors — the clock typically starts from the date the contract is completed, abandoned, or the last day on which you supplied services or materials under the contract.
• Suppliers — generally the last day on which you supplied materials to the project.
• Employees — specific rules apply based on the last day of work.

The critical point is that the 60-day period is calculated differently depending on the type of project, whether a certificate of substantial performance has been published, and your specific contractual relationship to the project. These nuances matter enormously. A day's error in identifying the trigger can mean the difference between a valid lien and no lien at all.

What happens if you miss the preservation deadline

The answer is simple and harsh: the right to register a lien is lost. There is no grace period. There is no ability to bring a motion asking the court to overlook the delay. The Construction Act extinguishes the lien right entirely once the deadline passes. You may still have other claims — a breach of contract action, a claim in unjust enrichment — but you lose the powerful in rem remedy that attaches to the land itself and creates genuine pressure on the property owner.

Stage Two: Perfecting the Lien

What "perfecting" means

Preserving a lien gets it onto title, but that registration alone does not keep it there indefinitely. To perfect a lien, you must take two additional steps:

1. Start a court action — commence a statement of claim in the Superior Court of Justice asserting the lien claim.
2. Set the action down for trial — file the required documentation to place the matter on the trial list, or otherwise take the steps the Construction Act requires within the perfection period.

Perfecting transforms your lien from a registration on paper into an active court proceeding. Without it, the lien eventually lapses and can be discharged as if it never existed.

The perfection deadline

As of writing (verify immediately with a lawyer), the deadline to perfect a lien is generally 90 days from the date the lien was preserved — that is, 90 days from the date of registration. This is not 90 days from when you were hired, or 90 days from when the dispute started. It is 90 days from the specific date stamped on your registered lien document.

Consolidation with other lien actions

Where multiple lien claims have been registered against the same project, the Construction Act requires that those actions be consolidated — joined together in a single proceeding. This adds procedural complexity. Even if another party has already started a lien action against the same property, you must take steps to either join that action or ensure your lien is perfected within your own 90-day window. Do not assume someone else's lawsuit protects you.

What happens if you miss the perfection deadline

Again, the outcome is unforgiving. A preserved but unperfected lien expires. The owner or contractor can then move to have the registration vacated from title — effectively wiping your claim from the record. Any security posted to vacate the lien is also released. You are back to an ordinary unsecured claim, fighting in court without the leverage of a registered encumbrance on the land.

Why These Deadlines Are Different From Ordinary Limitation Periods

Ontario's general civil limitation period — the basic rules under the Limitations Act, 2002 — gives most plaintiffs two years to start a lawsuit. Construction lien deadlines are shorter, stricter, and governed by their own statute. They cannot be extended by agreement between the parties, tolled by ongoing negotiations, or rescued by a court exercising its discretion. Negotiations, promises of payment, and partial cheques do not pause the clock.

This is the reason experienced construction lawyers will tell you the same thing: start the lien process the moment payment is seriously overdue. Waiting to see whether the other side comes around is the most common way valid lien rights are lost.

A Timeline at a Glance

Frequently asked questions