Discovery is narrower, juries are rare, and the loser pays. Here is how a civil action moves through the Ontario Superior Court of Justice, and the differences that most often catch U.S. lawyers by surprise.
U.S. clients and their counsel are often surprised by how different Ontario litigation feels, despite the shared common law tradition. Pleadings look familiar. Almost everything after them is calibrated differently: what must be produced, who can be examined and for how long, who decides the case, and who pays for it. This guide sets out the structure of a civil action in Ontario's Superior Court of Justice and flags the points where U.S. assumptions most often lead clients astray.
Rule references are to Ontario's Rules of Civil Procedure, RRO 1990, Reg 194 (cited as "r."), and to the Courts of Justice Act ("CJA"). Dollar amounts are in Canadian dollars.
Canada has a federal court system and a separate court system in each of its 10 provinces and 3 territories. Canada's federal courts have much narrower jurisdiction than U.S. federal courts. There is no general federal-question or diversity jurisdiction; the Federal Court hears mainly judicial review of federal tribunals (including immigration decisions), maritime law, claims against the federal Crown and certain intellectual property matters, much of it shared with the provincial courts. Most commercial disputes are heard in the provincial superior courts, which have general jurisdiction over both provincial and federal law.
Three features of the provincial superior courts have no exact U.S. equivalent. Their judges are appointed by the federal government, but the courts are run by the province. They decide questions of both provincial and federal law. And their decisions are ultimately reviewable by the Supreme Court of Canada on any question, including pure questions of provincial law. In Alberta, Saskatchewan, Manitoba and New Brunswick, the superior court is called the Court of King's Bench (renamed from Queen's Bench in 2022). In Toronto, the Superior Court's Commercial List is a dedicated list for insolvency, receivership and corporate and commercial matters arising in the Toronto Region.
There is no multi-district litigation procedure. If the same dispute arises in two provinces, the Federal Court does not take jurisdiction; both provincial courts may hear it, and overlapping proceedings are managed through cooperation between counsel or by the courts.
The U.S. column describes federal practice; state rules vary.
Ontario has two kinds of civil proceeding. An action follows the familiar path of pleadings, discovery and trial. An application is decided by a judge on affidavit evidence, usually without live witnesses. Applications are available for specified kinds of relief, such as interpreting a contract or obtaining certain corporate remedies, and in any matter unlikely to involve material facts in dispute requiring a trial r. 14.05(3). Every proceeding is an action unless a statute or the Rules provide otherwise. The stages of an ordinary action look like this:
Interlocutory motions are heard by judges or by associate judges (formerly "masters"), and are decided on affidavit evidence, with cross-examination on the affidavits and, often, written argument in a factum (mandatory on summary judgment motions). Since December 2024, every factum must certify that the authorities cited are authentic; since September 1, 2026, it must also certify that every quotation is accurate r. 4.06.1(2.1). Summary judgment is available where there is no genuine issue requiring a trial, and motion judges have expanded powers to weigh evidence and assess credibility r. 20.04(2)–(2.2); Hryniak v Mauldin, 2014 SCC 7 at paras 44, 49, 66.
In Toronto, Ottawa and Essex County, the court can assign an action to case management, where a judge or associate judge sets and enforces a timetable r. 77.02. Case management is reserved for cases with a demonstrated need.
Filing is online (in Toronto through the Ontario Courts Public Portal), documents for hearings are shared with the court through the Case Center platform, and service between lawyers is routinely by email. The party scheduling a hearing proposes whether it will be in person, by telephone or by video, and the court decides if another party objects r. 1.08. For U.S. clients, this means witnesses and client representatives can often attend without travelling to Toronto.
Discovery is where U.S. expectations most often need resetting. Each party must disclose every document relevant to a matter in issue that is or has been in its possession, control or power, whether helpful or harmful r. 30.02, 30.03. The matters in issue are defined by the pleadings. In practice, a party's own relevance review stands unless the other side challenges it.
Each party may examine each opposing party once. For a corporate party, that means a single representative unless the parties agree or the court grants leave, which is difficult to obtain. Unlike a Rule 30(b)(6) deposition, the examining party chooses which officer, director or employee to examine; the corporation can have someone else substituted only by a court order obtained before the examination r. 31.03(2). Questions may range over any matter in issue r. 31.06. Questions a witness cannot answer personally are typically met with an undertaking to provide the information later.
Evidence and documents obtained through discovery in Ontario may be used only for the purposes of the Ontario proceeding, subject to limited exceptions (for example, material filed with the court or used at a hearing) r. 30.1.01(3)–(6). If your client is running parallel litigation in the U.S., Ontario discovery cannot simply be imported into it. Plan early for the disclosing party's consent or a court order, which requires the interests of justice to outweigh any prejudice r. 30.1.01(8).
A U.S. client sitting for an Ontario examination for discovery should expect a shorter, more focused process than a deposition, but the transcript carries real weight: the opposing party may read admissions from it into evidence at trial. The advice we give our own witnesses applies:
The single largest adjustment for U.S. clients is that the loser usually pays part of the winner's legal costs, on motions as well as at trial. The court has broad discretion over whether costs are awarded, in what amount and when. The factors include the amount at stake and recovered, the complexity and importance of the issues, the parties' conduct, and any written offers to settle r. 57.01(1).
Costs exposure should be part of every budget and settlement discussion. It also changes the economics of settlement through Rule 49. A formal offer that is not accepted, and is then matched or beaten at the hearing, shifts costs from the date the offer was served, unless the court orders otherwise:
The plaintiff obtains a judgment as good as or better than its own offer.
The plaintiff wins, but obtains a judgment no better than the defendant's offer.
Settlement communications are conducted "without prejudice", meaning they generally cannot be used against a party if the matter does not settle. A party may settle with one defendant and continue against the others.
Ontario channels lower-value claims into streamlined procedures, based on the amount claimed exclusive of interest and costs.
Final orders can generally be appealed as of right. Interlocutory orders of a judge can be appealed only with leave; interlocutory orders of an associate judge can be appealed to a Superior Court judge without leave CJA s. 17; r. 62.01. Which court hears the appeal depends on the type and size of the order. A further appeal to the Supreme Court of Canada requires that court's leave, which is granted in a small number of cases of public importance.
Appellate courts review questions of law for correctness, but will disturb a trial judge's findings of fact only for "palpable and overriding error": Housen v Nikolaisen, 2002 SCC 33 at paras 8, 10.
Ontario class actions must be certified. The court must find a cause of action, an identifiable class, common issues, a suitable representative plaintiff with a workable litigation plan, and that a class proceeding is the preferable procedure CPA s. 5(1). For plaintiff class actions started on or after October 1, 2020, amendments require that a class action be superior to all reasonably available alternatives and that common issues predominate over individual ones CPA s. 5(1.1), a test U.S. counsel will recognize from Rule 23(b)(3). A class action must be dismissed for delay on motion unless, within one year of commencement, the plaintiff has filed a complete certification motion record or a timetable has been agreed or set CPA s. 29.1. Orders granting or refusing certification are appealed directly to the Court of Appeal CPA s. 30(1).
The basic limitation period is two years from the day the claim was discovered: when the claimant knew, or reasonably ought to have known, of the loss, who caused it, and that a proceeding would be appropriate. An ultimate period of 15 years runs regardless of discovery Limitations Act, 2002, ss. 4, 5, 15. Limitation periods were suspended from March 16 to September 13, 2020 inclusive, which can still matter for older claims. Some claims have no limitation period and some statutes set their own.
A defendant sued over expression on a matter of public interest can move for early dismissal. Once the defendant shows the claim arises from such expression, the claim proceeds only if the plaintiff shows grounds to believe it has substantial merit and the defendant has no valid defence, and that the harm to the plaintiff outweighs the public interest in protecting the expression. The action is stayed while the motion is pending, and a successful moving party presumptively recovers full indemnity costs CJA ss. 137.1–137.2.
Ontario is partway through a fundamental review of its civil rules. The Civil Rules Review's Final Policy Report (October 2025) recommends an "up-front evidence" model in which parties exchange the documents they rely on and sworn witness statements early, much shorter oral examinations, three procedural tracks replacing summary judgment and the simplified procedure, early fixed hearing dates, and province-wide mandatory mediation.
None of the structural recommendations has been enacted, and the current Rules continue to apply. In May 2026, the Attorney General and former Chief Justice Morawetz of the Superior Court announced in a joint statement that reform will be phased in, starting with targeted amendments (to service, default judgment, refusals and motion materials, among others). Because Ontario actions often run for several years, the rules may change while a case is underway.
