- Breach of contract asks a court to enforce a bargain: there was a valid agreement, one side didn't hold up their end, and you're entitled to what the contract promised (or damages…
- Litigation involves real uncertainty about how a court will characterize the facts.
- Ontario's Rules of Civil Procedure allow claims to be pleaded in the alternative — you're not required to commit to a single legal theory before you know how the facts will be found.
You believe you have a contract, and you believe the other side broke it. But what if a court later decides the agreement was never properly formed, was too vague to enforce, or didn't cover what actually happened? If your entire case rests on breach of contract alone, that outcome can leave you with nothing — even though you were clearly out of pocket.
This is why Ontario plaintiffs frequently plead unjust enrichment alongside breach of contract, as a backup claim rather than a replacement for it. Understanding when and why to do this can be the difference between a case that survives a shaky contract argument and one that collapses with it.
The Basic Difference Between the Two Claims
Breach of contract asks a court to enforce a bargain: there was a valid agreement, one side didn't hold up their end, and you're entitled to what the contract promised (or damages standing in its place).
Unjust enrichment doesn't depend on there being an enforceable contract at all. It asks whether the other side received a benefit at your expense, with no legal justification for keeping it. It's a fallback rooted in fairness rather than bargain-keeping.
| Breach of Contract | Unjust Enrichment | |
|---|---|---|
| Requires a valid, enforceable contract? | Yes | No |
| What's recovered | The benefit of the bargain (contract price or damages) | The value of the benefit conferred |
| Typical trigger for use | Contract terms are clear and enforceable | Contract is missing, disputed, incomplete, or void |
| Central question | Did they breach what was agreed? | Would it be unfair for them to keep what they received? |
Why Plaintiffs Plead Both
Litigation involves real uncertainty about how a court will characterize the facts. Common situations where pleading both makes sense:
- The existence of a contract is disputed. The other side denies an agreement was ever finalized, or says key terms were never settled.
- The contract's validity is in question. It might be unenforceable for a technical reason — for instance, a category of agreement that Ontario's Statute of Frauds requires to be in writing, and it wasn't.
- The contract may not cover the specific work or dispute. Extra work outside the written scope is a common source of this gap.
- There's a real risk the contract will be found void, frustrated, or terminated in a way that leaves a benefit unaccounted for.
In each case, pleading unjust enrichment in the alternative means that if the breach of contract claim fails on a technicality, the court can still consider whether it would be unfair for the other side to keep what they received.
How This Plays Out in a Statement of Claim
Ontario's Rules of Civil Procedure allow claims to be pleaded in the alternative — you're not required to commit to a single legal theory before you know how the facts will be found. A typical structure:
- Set out the facts of what happened, described neutrally so they support either theory.
- Plead breach of contract as the primary claim, identifying the agreement and how it was broken.
- Plead unjust enrichment in the alternative, in case the contract claim doesn't succeed.
- Claim relief that covers both possibilities, so the pleading isn't limited to contract damages alone.
A court generally addresses the contract claim first. It only turns to unjust enrichment if the contract claim doesn't succeed — you don't get to recover under both theories for the same loss.
A Practical Example
Say a contractor and homeowner exchange emails about a renovation, start work, but never sign a final written contract before a dispute erupts over scope and price. The contractor sues for breach of contract, arguing the email exchange formed a binding agreement.
If a court decides the emails were too vague to form an enforceable contract, a pure breach of contract claim fails outright. But if the contractor also pleaded unjust enrichment, the court can still consider whether the homeowner unfairly benefited from work performed and materials supplied — and order payment for the reasonable value of that work.
Points to Keep in Mind
- [ ] Pleading both is not "double-dipping" — you generally can't recover twice for the same loss
- [ ] The stronger and more consistent your factual narrative, the better it supports either legal theory
- [ ] Weak documentation of a contract is exactly when an unjust enrichment backup matters most
- [ ] Evidence of the value of work done or benefit conferred matters for the unjust enrichment claim, separate from proving the contract's terms
- [ ] The right court (Small Claims Court, Simplified Procedure, or ordinary Superior Court process) depends on the amount claimed, whichever theory ultimately succeeds
Frequently asked questions
Can I recover under both claims at the same time?
No. Alternative pleading means the court will only award a remedy under one theory — usually whichever one succeeds and provides the more complete recovery. You're preserving options, not stacking claims.
Does pleading unjust enrichment weaken my breach of contract claim?
Not if it's drafted properly. Pleading in the alternative is a standard, accepted litigation technique. It signals prudence about factual uncertainty, not doubt about your primary claim.
What if there clearly is a valid written contract?
Then unjust enrichment usually isn't needed or available for the same subject matter — a valid, enforceable contract that covers the dispute is generally treated as the "legal reason" that defeats an unjust enrichment claim. It becomes more relevant when the contract's existence, validity, or scope is genuinely in doubt.
Do I need a lawyer to plead a claim this way?
You can plead claims yourself in Small Claims Court, but structuring alternative claims correctly — so they support each other rather than undermine your credibility — is exactly the kind of drafting where legal advice tends to pay for itself, especially for larger or more complex disputes.
This is a litigation question
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