What Is a Limitation Period in Ontario? Strype Explains

If you've been hurt because of someone else's carelessness, you might assume you have all the time in the world to sort out your legal options. That assumption can cost you your entire claim. Ontario law gives you a limited window to start a lawsuit, and once that window closes, the courts will almost never let you back in, no matter how strong your case would have been.

This is what lawyers call a limitation period, and understanding how it works matters just as much as understanding your injury itself. Whether you were hurt in a car accident, harmed during a medical procedure, or denied disability benefits you were counting on, the clock is already running on your right to sue. Knowing when that clock started, and when it runs out, is one of the most important pieces of information you can have right now.

Key Takeaways

• A limitation period in law is the legal deadline for starting a lawsuit, and in Ontario the basic rule is two years from when the claim is discovered.
• The clock often doesn't start on the date of the accident. It starts when you reasonably knew about the injury, its cause, and who's responsible.
• A separate 15-year ultimate limit applies regardless of discoverability, though minors and Family Law Act claims have their own rules.
• Missing your limitation period generally ends your right to sue, even if your case would have been strong.
• Because every case is different, the safest step is to speak with a personal injury lawyer as soon as possible after you're hurt.

What Is a Limitation Period in Law?

A limitation period is the window of time the law gives someone to start a lawsuit after being harmed. Once that window closes, the injured person generally loses the right to sue, regardless of how strong the underlying claim might have been.

In Ontario, most personal injury claims fall under a two-year limitation period, though the exact deadline depends on the type of claim.

Limitation periods exist in every Canadian province, but the rules aren't the same everywhere. Each province has its own statute of limitations, with its own deadlines, exceptions, and starting points. In Ontario, these rules come from the Limitations Act, 2002, the piece of legislation that sets out how long you have to bring most civil claims, including personal injury lawsuits.

These deadlines aren't arbitrary. They exist because evidence gets weaker with time. Witnesses move away or forget what they saw. Physical evidence gets lost or destroyed. Medical records can be harder to interpret years after an injury. Limitation periods also give defendants some certainty. At some point, people and businesses need to know they won't be sued over something that happened long ago. Balancing fairness to injured people against fairness to defendants is the whole reason these laws exist.

Ontario's Basic Two-Year Limitation Period

Under the Limitations Act, 2002, the basic limitation period in Ontario is two years from the date a claim is discovered. For most personal injury cases, this means you generally have two years from the date of your accident or injury to start a lawsuit. But as the next section explains, the discovery date isn't always the same as the date something happened to you.

This two-year rule is a significant change from Ontario's older common law approach, which relied on a patchwork of different deadlines depending on the type of claim. Before the current Limitations Act took effect in 2004, limitation periods varied widely and were often difficult to pin down. The modern law was designed to create one clear, general rule that applies across most types of civil claims, with specific exceptions carved out where they're needed.

Here's how the basic limitation period breaks down across common claim types:

The 10-Day Written Notice Requirement for Municipalities

Under Section 44(10) of the Municipal Act, 2001 (and Section 42(6) of the City of Toronto Act, 2006 for Toronto specifically), anyone injured due to non-repair or snow/ice on a municipal road, bridge, or sidewalk must serve written notice of the claim—including the date, time, and exact location—to the municipal clerk within 10 days of the incident.

The 10-day rule is a notice requirement, not the deadline to actually file a lawsuit in court. Providing written notice preserves your right to sue later within the standard 2-year limitation period established under the Limitations Act, 2002.

Under Section 44(12) of the Municipal Act, 2001, failing to give notice within 10 days will not automatically bar a lawsuit if:

1. The injured person has a reasonable excuse for the delay (e.g., severe physical or mental incapacity, surgery, or hospitalization following the injury).
2. The delay does not prejudice (hurt or weaken) the municipality's ability to defend itself (i.e., the municipality can still investigate the conditions/evidence effectively).

The Discoverability Rule and How It Applies to Your Claim

The two-year clock doesn't necessarily start on the date of your accident or medical procedure. Under a legal principle called discoverability, the clock starts when you reasonably knew, or ought to have known, the following three things:

1. That you were injured.
2. That the injury was caused by someone else's act or omission.
3. That a lawsuit would be an appropriate way to seek a remedy.

This principle was clarified by the Supreme Court of Canada in Grant Thornton LLP v. New Brunswick, which set out the modern legal standard for when a claim is considered discovered. The court confirmed that discovery requires more than a suspicion of harm. It requires enough knowledge that a reasonable person would have grounds to start a legal proceeding.

This matters enormously for injury victims because the clock may start later than you think, but you should never assume it has. Waiting to find out is a risk you don't need to take. A lawyer can assess your specific facts and tell you where you stand, often within a single consultation.

Motor Vehicle and Catastrophic Injury Claims

Not every injury from a car accident is obvious right away. A delayed diagnosis of a traumatic brain injury or spinal cord injury can shift the discovery date well past the accident itself. Someone who felt shaken but otherwise fine after a collision may not learn the full extent of a brain injury until symptoms worsen months later. In these cases, the two-year clock may not start until the diagnosis connects the injury to the accident.

Medical Malpractice and Birth Injury Claims

Harm from a medical error often surfaces long after the treatment that caused it. A surgical complication might not be identified until a follow-up procedure years later. A birth injury like cerebral palsy may not be fully understood until developmental delays become apparent as a child grows. This is exactly where Strype's in-house nursing staff makes a meaningful difference. Because the team reviews complex medical files internally before bringing in outside experts, families get a clearer, faster answer about when their claim was actually discovered and how much time they realistically have.

Long-Term Disability Claims

For long-term disability claims, discovery typically runs from the date your insurer denies your claim, not from the date you stopped working or first became disabled. This distinction was central to MacIvor v. Manulife, a landmark Supreme Court of Canada case that shaped how LTD claims are evaluated in Ontario. If your benefits were denied, the two-year clock likely started on the date of that denial letter, which means the deadline can arrive faster than many people expect.

The 15-Year Ultimate Limit and Claims With No Deadline

Discoverability can push the two-year clock back, sometimes by years. But it doesn't push it back forever. Section 15 of the Limitations Act sets a 15-year ultimate limitation period that runs from the date the act or omission that caused the harm actually occurred, regardless of when it was discovered. Once 15 years have passed, a claim is generally barred even if the injury was only discovered recently.

There's an important pause built into this rule. The limitation clock doesn't run while the injured person is a minor or lacks the legal capacity to manage their own affairs, such as in cases involving severe cognitive impairment. For a child injured in a car accident, for example, the two-year clock typically doesn't start until they turn 18, giving families more time to assess long-term effects before a deadline applies.

Family Law Act claims work differently again. Claims brought by a spouse, child, or parent for loss of care, guidance, and companionship following a loved one's serious injury or death are exempt from both the two-year basic limit and the 15-year ultimate limit, provided they're brought alongside the injured person's own claim. This is a nuanced area of the law, and families in this situation should get specific legal advice rather than relying on general rules.

Employment claims work on a separate track. A wrongful dismissal claim still follows the standard two-year rule from the date of termination, without the extended timelines that can apply to injury cases.

The table below summarizes how these deadlines apply, or don't apply, across a few common scenarios:

Limitation Periods in Other Areas of Law

The rules above apply to most civil claims in Ontario, but they aren't universal. Claims against the Crown, meaning federal or provincial government bodies, and claims under certain federal statutes follow separate rules outside the provincial Limitations Act. These claims often carry their own notice requirements and deadlines, and they can be shorter than the standard two-year window. If your injury involved a government body, get legal advice quickly.

It's also worth understanding how limitation periods work differently in criminal law. Most criminal offences in Canada have no limitation period at all, meaning charges can technically be laid years or even decades after the fact. This is a completely separate process from a civil claim for injury arising from the same event. If you were hurt in an assault, for example, the criminal case against the person who hurt you and your own civil claim for compensation are two different legal tracks with two different sets of rules and two different limitation periods.

Strype Injury Lawyers handle the civil side of these matters. Our focus is recovering compensation for your injuries, your losses, and your future care needs. We don't manage criminal prosecutions, but we work alongside that process when it's relevant to building your case.

Conclusion: Don't Let Time Run Out on Your Claim

Limitation periods exist for good reasons, but they can also work against injured people who don't know their rights. The basic two-year rule sounds simple, yet discoverability, the 15-year ultimate limit, and the exceptions for minors and Family Law Act claims all shape when your specific deadline actually falls. Waiting to find out where you stand is one of the costliest mistakes an injured person can make.

You don't need to figure this out on your own, and you don't need to have all the answers before you call. At Strype Injury Lawyers, we'll review the facts of your situation, tell you honestly where your limitation period stands, and explain your options in plain language. There's no cost and no obligation for that conversation, and we only take cases we believe we can win.

Here's what to do if you're not sure where you stand.

1. Gather what you have, including medical records, incident reports, and any correspondence with insurers.
2. Write down the date you first learned about your injury and its cause, even if that date is different from the incident itself.
3. Call a personal injury lawyer before you assume it's too late. Discoverability may have extended your deadline.
4. Ask directly about your limitation period during your free consultation so you know exactly where you stand.

Don't talk to the insurance company. Talk to us. Contact Strype Injury Lawyers today for a free, no-obligation case evaluation.

Legal Disclaimer: The information in this article is intended for general educational purposes only and does not constitute legal advice. Every personal injury claim is unique, and the facts of your situation may affect your legal rights and options. If you have been injured or believe you may have a legal claim, contact a qualified personal injury lawyer in Ontario as soon as possible.