When must mandatory mediation happen in the Ontario litigation timetable?

Under Rule 24.1 of the Rules of Civil Procedure, mandatory mediation in Ontario must take place within 180 days after the first defence is filed in a case managed action in Toronto, Ottawa, or Essex County. This deadline can be extended by consent of the parties or by a court order, but the default is to have mediation completed relatively early in the litigation.

The 180-day window was designed to encourage early resolution before the parties have incurred the full cost of discoveries, expert reports, and motions. Early mediation sometimes works best when parties have not yet entrenched their positions through extended litigation; however, some parties prefer to conduct at least documentary discovery before mediating so they have a clearer picture of the other side's evidence.

If mediation is not completed within the required time and no order has been obtained extending the deadline, the court can impose consequences for non-compliance, including striking a defence or dismissing a claim in extreme cases. In practice, extensions are routinely granted by consent. Outside the mandatory mediation regions, parties can agree to mediate at any time, and they can choose the timing that makes the most strategic sense for their case.