Boundary Disputes Between Neighbours in Ontario: What You Need to Know

When you and your neighbour disagree about where one property ends and the other begins, you are dealing with a boundary dispute — one of the most common and emotionally charged property conflicts in Ontario. Whether the argument started over a new fence, a shed placed too close to the lot line, or a survey that produced different results than expected, these disputes can escalate quickly and become expensive if handled poorly.

This article explains how Ontario law addresses boundary disputes, what evidence matters, and what paths are available to resolve the conflict — from a conversation over the fence to a full court proceeding.

Why Boundary Disputes Happen

Most boundary disagreements are not about bad faith. They arise because:

• Older surveys used different measurement technology and may not line up with modern GPS-based surveys.
• Registered title in Ontario's land titles system depends on the documents that were filed, not always on physical markers on the ground.
• Fences and hedges that have stood for decades may not follow the true legal property line.
• Chains of title sometimes contain description errors that were never corrected.

Until someone builds, renovates, or sells, these discrepancies can go unnoticed for years.

The Legal Framework: Ontario's Boundaries Act

Ontario's Boundaries Act provides a formal administrative process for resolving uncertainty about a boundary. Under that legislation, a land owner can apply to have the boundary between two parcels officially established by a provincial land surveyor acting as a surveyor/arbitrator. The process:

1. A licensed Ontario land surveyor is appointed.
2. The surveyor examines title documents, prior surveys, physical evidence, and statements from the parties.
3. The surveyor issues a decision establishing the boundary, which is then registered on title.

The Boundaries Act process is faster and cheaper than a full court trial and produces a result that is binding on both owners. However, if either party has concerns about the surveyor's decision, there are appeal rights — verify current appeal timelines with a lawyer, as they are time-limited.

Getting a Survey: The Starting Point

Before spending money on legal proceedings, get a survey by a licensed Ontario land surveyor (OLS). The survey should:

• Locate existing registered title documents and plans.
• Search for physical monuments (iron bars, survey pins, concrete bars).
• Produce a written surveyor's report explaining how the boundary was determined.

A survey does not by itself resolve a dispute — but it gives both parties authoritative evidence to work from. Often, once an independent survey is in hand, one party recognizes they were mistaken and the dispute ends.

When the Dispute Does Not Settle

If the survey does not end the argument, your options include:

Negotiation and Boundary Agreements

Neighbours can agree to a boundary line agreement — a document signed by both parties and registered on title that formally settles where the boundary is. This is inexpensive and avoids court. A lawyer drafts and registers the agreement.

Mediation

A neutral third party helps facilitate a negotiated resolution. Mediation is non-binding unless the parties reach an agreement and sign a settlement. It preserves the relationship better than litigation.

Litigation in the Superior Court of Justice

If negotiation fails, either party can bring an application or action in Ontario's Superior Court of Justice to determine the boundary. The court will consider:

• Registered title documents and plans of survey.
• Prior surveys and plans.
• Physical monuments and occupation evidence.
• Historical usage (though adverse possession, discussed in a separate article, has limited application in land titles areas).

Court proceedings are costly and slow. Reserve litigation for situations where the stakes justify it — for example, where a significant structure or sale is at stake.

Evidence That Matters in a Boundary Case

Strong boundary cases are built on documentation:

Practical Tips for Neighbours

• Do not move or remove survey pins. Interfering with survey monuments is an offence under provincial law.
• Document everything early. Take photographs of fences, hedges, and structures with timestamps.
• Do not start construction on disputed land until the boundary is confirmed.
• Get independent legal advice before signing any agreement that gives up rights — even an informal one.

Frequently asked questions