An interlocutory injunction is temporary relief granted before the underlying dispute has been finally determined. A permanent injunction is final equitable relief granted after the parties’ legal rights have been adjudicated. The distinction affects both the legal test and the evidentiary basis on which the court acts.
What is an interlocutory injunction?
An interlocutory injunction operates while the underlying proceeding is still pending. Its purpose is generally to protect rights, prevent harm, or preserve an appropriate position until the court can finally determine the dispute.
Because the court has not yet finally adjudicated the parties’ substantive rights, a conventional interlocutory injunction that restrains conduct is generally assessed under the RJR—MacDonald framework.
The moving party must ordinarily establish:
- a serious question to be tried;
- irreparable harm if interim relief is refused; and
- that the balance of convenience favours granting the injunction.
For the complete framework, see What do you have to prove to get an interlocutory injunction in Ontario?.
The applicable first-stage threshold can be more demanding where the requested interlocutory order requires positive action rather than merely restraining conduct.
What is a permanent injunction?
A permanent injunction is different because it forms part of the court’s final disposition of the parties’ rights.
The Ontario Court of Appeal explained the distinction in 1711811 Ontario Ltd. (AdLine) v. Buckley Insurance Brokers Ltd., 2014 ONCA 125. A court considering permanent injunctive relief is no longer deciding whether temporary protection should be imposed while the merits remain unresolved. The underlying legal rights must instead have been finally determined.
In that setting, the court considers whether:
- the claimant has established the legal right on which the requested relief depends;
- damages or another remedy would be inadequate; and
- there is any equitable or discretionary reason why the injunction should not be granted.
A successful claim does not therefore make a permanent injunction automatic. Injunctive relief remains an equitable remedy and the proposed order must be justified by the rights that have actually been established.
See Can you get a permanent injunction after trial in Ontario? for the final-relief analysis.
Why does the distinction matter in practice?
The distinction determines more than how long the order lasts.
On an interlocutory motion, the court must decide whether intervention is justified before the merits have been finally determined. Issues such as irreparable harm and balance of convenience help the court manage that interim risk.
For a permanent injunction, the court has determined the underlying rights and must decide whether continuing court-ordered relief is an appropriate final remedy.
The evidence required may therefore be materially different. An interlocutory motion may proceed on a motion record prepared on an urgent timetable, while permanent relief ordinarily depends on the evidentiary and factual findings made through final adjudication.
Can an interlocutory injunction later become permanent?
The same dispute may involve both forms of relief, but an interlocutory injunction does not automatically become permanent simply because it was granted earlier.
A party seeking permanent injunctive relief must establish entitlement to that final remedy on the record and legal findings available at the final stage.
For an overview of the different forms of injunctive relief, see What types of injunctions are available in Ontario?.
How does ME Law assess interlocutory and permanent injunctions?
ME Law distinguishes between the immediate question of whether interim court intervention is required and the separate question of what final equitable relief should follow once the parties’ substantive rights have been determined.
That distinction affects litigation strategy, evidence, the scope of the proposed order, and the legal authorities that should be placed before the Superior Court of Justice.
For ME Law’s approach to final equitable relief, see Permanent Injunctions and Final Equitable Relief.
Contact ME Law if you are seeking or responding to interlocutory or permanent injunctive relief in Ontario.