How to Register a Construction Lien in Ontario

What a construction lien actually does

A construction lien is a claim registered against the title of a property by someone who supplied labour or materials to improve it and wasn’t paid. It secures your claim against the land itself. In plain terms, your lien says: “I improved this property, and I have a claim on it until I’m paid.” Owners can’t easily sell or refinance with one on title, which is exactly why liens get cheques written.

Not sure a lien is your best move? Start with what to do when you’re not paid — it compares every route by what ends up in your pocket. Already past the deadline? See missed the lien deadline.

Step 1: Know your deadline — and write down your last day

Liens live and die by two clocks, and they run in order. For contracts since July 1, 2018:

What starts the 60 days

• Write down your last day of real work on every job, the day it happens: what you did and what proves it. Courts decide it largely from your invoices — a visit you never invoiced is weak evidence.
• Callbacks don’t restart the clock. Coming back to fix a deficiency, warranty work, or picking up tools usually doesn’t count.
• Watch for certificates. Since January 2026 certificates of substantial performance are published on the Daily Commercial News, Link2Build or Ontario Construction News. Once published, the clock can start for everyone who supplied before it — seen or not.
• Old contracts, old rules. If the main contract or procurement started before July 1, 2018, the old Construction Lien Act and its 45-day clock apply.

Step 2: Gather the details — owner, land, work, dates

Liens fail on wrong details far more often than on the law. Pull the parcel register on OnLand ($36.50) and collect these before anyone registers anything:

Spend $8 on the Ontario Business Registry profile of whoever hired you too — you need its exact legal name, and its directors’ names if this turns into a trust claim.

Before you register: the written notice of lien

A written notice of lien (Form 1) goes to the payer above you — usually the owner or the GC. It forces them to hold back enough to cover your claim from what they pay down the chain, and it can stop a construction lender’s priority on further advances. That can freeze the money where you can reach it.

How much to lien for

Lien the value of what you supplied and haven’t been paid for, plus approved extras, minus credits for work not done and acknowledged deficiencies. Include holdback owed to you. Don’t lien the full contract price, interest, head-office markup, profit on work you never did, or materials that never arrived.

Step 3: Register (preserve) the lien

Liens on private land are registered electronically through Teraview, Ontario’s land registration system. Teraview uses licensed accounts and paper registration is only accepted in limited cases, so in practice:

• Most liens are registered by a construction lawyer. The Law Society has treated preparing and registering liens as lawyers’ work.
• Online lien-registration services exist. They run on what you type in — Ontario lawyers have warned that a wrong owner name or a missed trigger can sink the lien, and once it’s registered you can’t simply refile to fix it.
• Register well before day 60. The system stamps the date and time — your proof you were in time. Don’t call a lawyer on day 59.
• Public jobs are different. On municipal or provincial land the claim is given to the clerk or ministry and attaches to the holdback, not the land. Federal land can’t be liened — look for a payment bond.

Step 4: Perfect the lien within 90 days

Preserving puts the lien on title; perfecting makes it enforceable. Within 90 days after the last day you could have preserved, the lien has to be perfected: an action started in the Superior Court of Justice and a certificate of action registered on title. A company needs a lawyer for this part.

A lien can’t be enforced in Small Claims Court — lien actions start in the Superior Court.

What it costs to register a lien

Is it worth liening?

A lien is a tool, not a principle. The right question is what you’ll end up with.

Amount owed minus typical registration and perfection costs; leaves out your own time. Compare every route on the not-paid page.

What happens after you file

• The owner reacts. Owners who need to sell, refinance or draw on a loan usually pay, settle, or lean on the GC once a lien lands.
• Or they vacate it. The court will order the lien off title once enough money or security is paid in — generally the amount claimed plus security for costs (25%, capped at $250,000), or another amount the court finds reasonable.
• A vacated lien isn’t lost. Your claim moves from the land to the money or bond in court. You still have to perfect and pursue it — but now there’s money sitting there with your name on the claim.
• Most cases settle. When you’re paid, register a discharge promptly.

Things people get wrong

Keep current: the 2018 and 2026 changes

The Construction Lien Act became the Construction Act in 2018, with the 60-day and 90-day periods. Prompt payment and adjudication arrived October 1, 2019. Amendments in force January 1, 2026 added mandatory annual holdback release, tightened proper-invoice rules, let lien and trust claims be combined in one action, and opened liens to unpaid designers. The core 60/90 deadlines didn’t change. See the Ontario Construction Act, explained and holdback and the 2026 annual release.

Do you need a lawyer?

You can do most of the homework yourself — your date, the parcel register, the amount, the details. But registering through Teraview and perfecting in the Superior Court are realistically lawyer’s work, and a defective or inflated lien can come back at you. Doing it without help is like building a skyscraper with a butter knife: possible, but the room for costly error is enormous.

The Ontario Lien Handbook walks through every step — including a lien prep worksheet that turns a lawyer’s first call into a short one — and covers what to do if a lien is registered against you.

Questions trades ask

Not legal advice. This is general information from an Ontario builder, current to October 2026. Your dates and rights depend on your contract and your facts — confirm them with an Ontario construction lawyer before you rely on them. Read the Construction Act on ontario.ca.

Getting paid: the full set of guides