Force Majeure Clauses in Ontario: When Performance Is Excused

A force majeure clause is a contract term that excuses, suspends, or delays a party’s performance when a specific kind of event — one beyond that party’s reasonable control — makes performance impossible or impracticable. The phrase itself translates roughly to “superior force,” and the clause is meant to allocate the risk of truly extraordinary disruptions, like natural disasters, war, labour strikes, or government action, rather than leaving a party exposed to breach for something it had no realistic way to prevent.

What a force majeure clause actually covers depends entirely on its wording. Well-drafted clauses include a specific list of qualifying events — fire, flood, earthquake, war, terrorism, labour disputes, government orders, and sometimes a catch-all phrase like “or other events beyond the reasonable control of the parties.” That catch-all language matters more than it might seem, because Ontario courts generally read it as limited to events of a similar kind to those specifically listed, not as a broad excuse for any disruption at all.

Just as important as the list of events is what the clause requires once one occurs. Most force majeure clauses require the affected party to show that the event actually prevented performance, not merely that the event happened and performance also became harder for unrelated reasons. A supplier whose costs rose because of a listed event, for example, generally cannot rely on the clause if it could still have performed, just at a higher cost.

A consistent theme in Ontario case law is that force majeure clauses are interpreted narrowly, strictly according to their actual wording, rather than broadly according to their apparent purpose. If an event isn’t listed and doesn’t clearly fall within a catch-all phrase that’s tied to the listed categories, courts have generally been reluctant to stretch the clause to cover it, even where the party invoking it was genuinely affected by unusual circumstances.

This narrow approach extends to how courts assess whether an event actually prevented performance. It’s generally not enough to show that a listed event occurred somewhere in the chain of events leading to non-performance — the party relying on the clause usually has to draw a direct line between the event and its specific inability to perform. Vague or general hardship, even hardship connected to a real listed event, often falls short of that standard.

Force majeure is often confused with the common-law doctrine of frustration, but the two work differently. Force majeure is purely contractual: it exists only because the parties wrote a clause addressing it, and it only covers the events that clause lists or clearly contemplates. Frustration, by contrast, applies automatically under the common law, regardless of whether the contract says anything about it, when a supervening event — again, through no fault of either party — makes performance impossible or so radically different from what was originally bargained for that holding the parties to it would be unjust.

In practice, a contract with a force majeure clause will generally be assessed under that clause first, since the parties have specifically agreed on how to allocate this kind of risk. Frustration tends to come into play either when there’s no clause at all, or when the clause doesn’t cover the particular event that occurred, leaving the common-law doctrine as a fallback. Our guide to breach of contract in Ontario touches on how an excuse like this interacts with an otherwise straightforward breach analysis.

Both doctrines share a similarly narrow approach: Ontario courts don’t treat a contract becoming more expensive, less convenient, or less profitable as enough to excuse performance under either one. The bar is impossibility or a radical change in what performance actually requires, not mere hardship.

Most force majeure clauses impose a notice requirement on the party seeking to rely on them. Typically, that party has to give the other side prompt written notice describing the event, when it began, and its expected effect on performance, often within a specific number of days of the event occurring or becoming apparent. Some clauses also require ongoing updates while the event continues and a final notice once it ends.

These notice requirements aren’t a formality to be skipped. A party that experiences a genuine force majeure event but fails to give the notice the clause requires can find its claim weakened or defeated entirely, even though the underlying event would otherwise have qualified. Courts generally treat notice obligations the same way they treat other procedural requirements in a contract: strictly, according to what the clause actually says.

Disputes over force majeure clauses tend to follow a few recurring patterns. One is whether an event genuinely fits within the clause’s list or catch-all language — a business claiming a supply chain disruption, for instance, has to show the disruption itself falls within what the clause covers, not simply that global conditions were difficult. Another is causation: even where a listed event clearly occurred, the other side will often argue the party invoking the clause could still have performed through reasonable alternative means, such as sourcing from a different supplier or absorbing a short delay.

A third common dispute involves timing and notice — whether notice was given promptly enough, in the right form, and to the right recipient, and whether a delay in giving notice should be excused given the circumstances of the event itself. And a fourth involves scope: some clauses excuse only specific obligations, such as delivery timing, while leaving others, like payment, fully intact, and parties sometimes disagree about how far the excuse is meant to extend. A fifth, less obvious dispute involves the end of the triggering event: a party that keeps invoking force majeure well after the event has passed, without resuming performance, can find itself facing a breach claim for the period after the excuse should have ended.

These disputes are rarely resolved by general fairness arguments. Because force majeure is a creature of contract, the outcome in almost every case turns on a close, literal comparison between what actually happened and the specific words the parties chose when the contract was drafted — which is also why the clause is worth reading carefully long before any disruptive event occurs, not only after one has already begun.

If an unusual event is affecting your ability to perform under a contract, the starting point is the contract’s actual force majeure wording, not a general sense of what seems fair. Reading exactly which events are listed, whether a catch-all phrase might extend to your situation, and what notice the clause requires will generally tell you more about your position than any general rule of thumb.

From there, many of the same practical steps that apply to other contract disputes apply here too: documenting the event and its effects, giving any notice the clause requires promptly and in writing, and considering whether a direct conversation can resolve the issue before it escalates. Our guide to demand letters and broader contract disputes hub cover what typically comes next if the issue isn’t resolved informally, and our tools section may help with reviewing a specific clause’s wording.