A Canadian Construction Lien Notice is a formal written communication sent by a contractor, subcontractor, material supplier, or other lien claimant to the property owner advising them of the claimant's intention to assert construction lien rights against the real property. In Canada, construction lien rights are governed entirely by provincial legislation, and the terminology and requirements vary across provinces. Ontario uses the term 'construction lien' under the Construction Act (R.S.O. 1990, c. C.30, as amended by Bill 142 in 2018). British Columbia and Alberta use the term 'builders lien' under their respective Builders Lien Acts. Other provinces use various terms including 'mechanics lien.'

The construction lien notice serves several critical functions in the Canadian construction payment system. First, it provides the property owner with formal notice that a participant in the construction project has not been paid and intends to exercise their statutory lien rights. This is particularly important for subcontractors and material suppliers who have no direct contractual relationship with the property owner. Under Ontario's Construction Act, a subcontractor who gives written notice to the owner triggers the owner's statutory obligation to retain the holdback from future payments to the general contractor.

Second, the notice creates a documented record of the claim that can be used as evidence in subsequent legal proceedings. If the lien claimant ultimately needs to register a lien on the property title and commence a court action to enforce it, the notice demonstrates that the claimant took reasonable steps to resolve the payment dispute before resorting to formal legal remedies. Canadian courts look favourably on parties who attempt to resolve disputes before commencing litigation.

Third, the notice serves as a demand for payment that may resolve the dispute without the need for formal lien registration. Many construction payment disputes are resolved after the owner receives a lien notice, because the notice makes the owner aware that their property may be encumbered by a lien if payment is not made. The practical effect of a registered lien on property title is that the owner cannot sell, refinance, or mortgage the property without first dealing with the lien, which creates significant pressure to pay.

The notice should be sent well before the statutory deadline for preserving (registering) the lien, to give the owner a reasonable opportunity to make payment. In Ontario, the lien must be preserved within 60 days of the last day of supply. In BC, the deadline is 45 days from the date of completion or abandonment. In Alberta, it is also 45 days. Sending the notice promptly after payment becomes overdue maximises the time available for negotiation before the lien must be registered.

A Canadian Construction Lien Notice is needed whenever a contractor, subcontractor, material supplier, equipment rental company, labourer, or design professional has not been paid for work performed or materials supplied on a construction project in Canada. The notice is the first formal step in the construction lien process and should be sent as soon as payment becomes overdue.

General contractors who have submitted invoices or progress claims to the property owner and have not received payment within the contractually agreed-upon timeframe need to send a lien notice. In Ontario, the Construction Act's prompt payment provisions (Part I.1) require the owner to pay the general contractor within 28 days of receiving a proper invoice. If payment is not received within this timeframe, the general contractor should send a lien notice and prepare to preserve their lien rights.

Subcontractors face a particularly urgent need for construction lien notices because their lien rights depend on giving notice to the property owner. A subcontractor who has been hired by the general contractor to perform electrical, plumbing, HVAC, framing, drywall, roofing, or other specialized work has lien rights against the owner's property, even though the subcontractor has no direct contract with the owner. However, to fully protect these rights, the subcontractor should give written notice to the owner as soon as payment from the general contractor becomes overdue.

Material suppliers who have delivered construction materials (lumber, concrete, steel, fixtures, drywall, roofing materials, mechanical equipment) to a job site and have not been paid by the contractor or subcontractor who ordered them need to send notice to both the party who ordered the materials and the property owner. Under most provincial lien statutes, the material supplier's lien rights are based on the last date of supply, not the last date of delivery.

Equipment rental companies that have provided construction equipment (cranes, excavators, forklifts, scaffolding, temporary fencing) on a rental basis and have not been paid for the rental period should send a lien notice. Design professionals including architects, engineers, and surveyors who have provided professional services and have not been paid may also need to send notice, depending on the provincial legislation.

The lien notice is also strategically important even when a formal construction lien may not ultimately be filed. Sending a well-drafted lien notice demonstrates that the claimant is serious about pursuing their rights and often prompts immediate payment or negotiation. The notice creates leverage because the property owner knows that a registered lien will cloud the title and prevent any sale, refinancing, or other dealings with the property until the lien is resolved.

A comprehensive Canadian Construction Lien Notice must contain several essential elements to be effective and to support any subsequent lien registration and enforcement proceedings. The notice must clearly identify the lien claimant with their full legal name or registered business name, business address, phone number, and email address. The claimant's role on the project (general contractor, subcontractor, material supplier, equipment rental company, labourer, or design professional) must be specified, along with any applicable provincial contractor licence or registration number.

The property owner must be identified with their full legal name and mailing address. If the claimant is a subcontractor or supplier, the general contractor's information should also be included to establish the contractual chain. The notice should indicate whether the claimant was hired directly by the property owner or by the general contractor, as this affects the claimant's position in the construction payment hierarchy and the applicable holdback obligations.

The property against which the lien is being claimed must be described with sufficient detail for identification. This includes the municipal address, the legal description (lot and plan number, PIN or PID, Land Title Office reference, as applicable), the province or territory, and the municipality or regional district. The legal description should match the description on the property title, which can be obtained through a title search at the applicable Land Registry Office or Land Title Office.

The description of work performed, services rendered, or materials supplied must be detailed enough to establish the claimant's entitlement to a lien. This includes the nature and scope of the work, the dates when work first commenced and was last performed, and the contractual basis for the work. The dates are critical because they determine the statutory deadlines for preserving and perfecting the lien. Under Ontario's Construction Act, the lien must be preserved within 60 days of the last day of supply.

The financial details must be clearly stated in Canadian dollars (CAD), including the original contract amount, total payments received to date, and the balance due and owing (the lien amount). If the claimant is claiming interest on the unpaid balance, the interest rate must be clearly expressed as an annual percentage rate in compliance with the federal Interest Act (R.S.C., 1985, c. I-15). The Interest Act requires that interest at a rate exceeding 5% per annum must be expressed as an annual rate, otherwise the maximum rate is 5%.

Statutory holdback information should be included. Most provinces require the owner to retain a 10% holdback from each progress payment. The notice should remind the owner of their statutory obligation to maintain the holdback and advise that releasing the holdback prematurely may result in personal liability. In Ontario, the basic holdback is 10% of the price of services or materials as they are actually supplied.

The notice must reference the applicable provincial construction lien legislation. In Ontario, reference the Construction Act (R.S.O. 1990, c. C.30). In BC, reference the Builders Lien Act (S.B.C. 1997, c. 45). In Alberta, reference the Builders' Lien Act (R.S.A. 2000, c. B-7). The notice should state the claimant's intention to preserve and perfect the lien if payment is not received, and should include a demand for payment within a reasonable timeframe.