In most cases you have two years to start a civil lawsuit in Ontario, under the Limitations Act, 2002. This is called the basic limitation period, and it runs from the day you discovered your claim rather than from the day the event happened. Some claims follow a different period set by another statute, and a few have no limitation period at all, so two years is the general rule rather than a universal one.

The clock usually starts on the date you discovered the claim, not the date of the event. Under section 5, a claim is discovered on the earlier of when you actually knew, or when a reasonable person in your circumstances ought to have known, four things: that injury, loss, or damage occurred; that it was caused by an act or omission; that a particular person was responsible; and that a court proceeding would be an appropriate way to address it. The law presumes you knew all of this on the day the act or omission took place unless you prove otherwise.

Separate from the two-year period, Ontario has a fifteen-year ultimate limitation period under section 15. It runs from the day the act or omission took place, regardless of when the claim was discovered, and sets an absolute backstop after which most claims can no longer be brought. The fifteen-year clock can be paused in limited situations, such as while a claimant is a minor or incapable, or where the responsible party wilfully concealed the claim.

Yes, in specific situations the limitation clock can be suspended. It is paused while a potential claimant is a minor (section 6) or is incapable of starting a proceeding (section 7) and has no litigation guardian to act for them, and while both parties have agreed to use an independent third party, such as a mediator, to try to resolve the claim (section 11). A signed written acknowledgment of liability can restart the clock for certain debt and property claims (section 13), and the parties can agree in writing to suspend or extend the period through a tolling agreement (section 22).

Yes. Section 16 lists claims that have no limitation period, including proceedings based on a sexual assault, certain assaults in a dependent or intimate relationship, claims seeking only a declaration, proceedings to enforce a court order, and claims to obtain or enforce support under the Family Law Act. Even where no limitation period applies, it is still wise to act promptly, because long delay can weaken a claim through other legal doctrines.

No. Under section 19, a limitation period in another Ontario statute has no effect unless the provision is listed in the Schedule to the Limitations Act, 2002. The Schedule preserves dozens of special periods, including those in the Insurance Act, the Construction Act, and the Libel and Slander Act, which can be shorter or longer than two years and may carry their own notice requirements. If you think a special period might apply, check our Special Limitation Periods tool and the specific statute.

If the limitation period has expired, your claim is generally statute-barred, which means the other side can raise the missed deadline as a complete defence and the court can dismiss the claim no matter how strong it is on the merits. Because the deadline often turns on the contested question of when the claim was discovered, you should not assume it is too late without advice. If a deadline may be approaching or recently passed, speak with a qualified Ontario lawyer as soon as possible.