How to Prove Unjust Enrichment Under New York Law

To prove unjust enrichment in New York, you have to show three things: the other party received a benefit, that benefit came at your expense, and equity and good conscience will not let them keep it. The New York Court of Appeals set out that test in Mandarin Trading Ltd. v. Wildenstein, and every claim rises or falls on those three elements plus a handful of practical requirements around timing, the relationship between the parties, and whether a contract already covers the dispute.¹

The Three Elements

Element one is enrichment. You need to identify a concrete benefit the defendant received: money, services, property, or something else of value. Vague claims that someone “profited generally” from a situation will not carry a court.

Element two is that the enrichment came at your expense. This usually means money you paid, work you performed, or property you transferred without the compensation you expected in return. The value that ended up with the defendant has to be traceable to something you gave up.

Element three is the one that decides most cases. Equity and good conscience must make it unfair for the defendant to keep the benefit. A judge will not order restitution just because value moved from one party to another. Courts look at whether the defendant knew about a mistake, encouraged your performance, or stayed silent while you delivered something valuable under a false assumption. Because this is an equitable doctrine, the judge weighs the overall fairness of the situation rather than running down a checklist. That flexibility is the doctrine’s strength, and it also makes outcomes less predictable than a straight breach of contract case.

Show a Real Connection Between You and the Defendant

You do not need a contract with the defendant to bring the claim. New York’s Court of Appeals has confirmed that privity is not required.² But there has to be some connection between the two of you. In Georgia Malone & Co. v. Rieder, the Court of Appeals held that the claim will not survive unless the relationship between the parties could have caused reliance or inducement on the plaintiff’s side.³

The practical consequence: you cannot sue a stranger who happened to benefit indirectly from something you did for someone else. Renovate a building for its owner and you generally cannot sue the neighboring business whose property value went up as a side effect. The Mandarin Trading court dismissed the claim in part because the defendant did not even know the plaintiff existed, which made the relationship “too attenuated” to support equitable relief.⁴ When you draft the complaint, spell out how the defendant knew of you, dealt with you, or accepted what you provided.

Watch for a Contract That Would Block the Claim

New York courts will not let you use unjust enrichment to work around a contract you do not like. If a valid, enforceable agreement covers the same subject matter, the claim gets dismissed.¹ Where parties negotiated specific terms, equity will not step in to rewrite the deal.

That rule creates a real problem when the contract’s validity is itself in dispute. New York handles this by letting you plead unjust enrichment as an alternative cause of action alongside breach of contract. You argue the contract is enforceable and was breached, and at the same time you argue that if the court disagrees, you are still owed restitution. If the judge finds the contract valid, the unjust enrichment claim drops away on its own. If the contract turns out to be void, unenforceable, or rescinded, you still have a path to recovery for the value you delivered.

File Within Six Years

You have six years to bring an unjust enrichment claim in New York. The limitations period falls under CPLR 213, which governs actions on quasi-contract.⁵ The clock generally starts when the enrichment occurs, not when you discover it, though exceptions can apply on the facts. Six years sounds generous, but these disputes often simmer for years before anyone calls a lawyer, and evidence of what was promised or expected gets harder to reconstruct with each passing year.

What You Can Actually Recover

The remedy is restitution. You are asking the court to return the value of the benefit, not to compensate you for lost profits or the deal you expected. That makes the recovery narrower than a typical breach of contract judgment.

Money Damages and Quantum Meruit

The most common remedy is a money judgment for the reasonable value of what you provided. Courts often frame this as quantum meruit, meaning “as much as was deserved.” The judge looks at market rates for the services or goods, what similar work costs in the industry, and the expenses you actually incurred. The court is not bound by the price you had in mind. It decides what the benefit was reasonably worth.

Interest works differently than in contract cases. Because unjust enrichment is equitable, CPLR 5001 gives the court discretion over whether to award interest, what rate applies, and what date it runs from.⁶ In contract actions, interest accrues automatically at 9% per year under CPLR 5004.⁷ Judges can use that 9% figure as a benchmark in unjust enrichment cases, but they are not required to, and they decide whether the facts justify interest at all.

Constructive Trust or Equitable Lien

When the dispute involves specific property rather than a general sum of money, courts can impose a constructive trust. That remedy declares that the defendant holds the property for your benefit and must turn it over. New York courts look at four factors: whether a confidential or fiduciary relationship existed, whether a promise was made, whether property was transferred in reliance on that promise, and whether the defendant was unjustly enriched. The factors are flexible guidelines, so a strong showing on some can offset weakness on others.

An equitable lien is a related option. Instead of transferring the property outright, the court places a lien on it, securing your interest up to the value of what was lost. A lien tends to fit better when the property has decreased in value, because it lets you pursue a deficiency judgment for the shortfall. A constructive trust gives you the property itself, including any appreciation.

Defenses You Need to Anticipate

A defendant has several standard ways to defeat the claim, and some of them catch plaintiffs off guard.

A valid contract governs the dispute. This is the most common defense and often appears on a motion to dismiss before trial.
The benefit was a gift. If the defendant can show you intended to confer the benefit without expecting payment, there is nothing unjust about keeping it. Courts look at the context of the transfer, communications about compensation, and whether a reasonable person would have expected payment.
Voluntary payment. Money paid voluntarily and without protest is generally not recoverable. If you knew what you were paying and chose to pay it, you cannot later recharacterize it as unjust. The defense fails if the payment was made under fraud, duress, or a mistake of fact.
Unclean hands. A defendant can argue you acted unfairly in connection with the same transaction. Courts will not help a plaintiff whose own conduct related to the benefit was inequitable.
Statute of limitations. More than six years since the enrichment ends the claim.⁵

Voluntary payment deserves extra attention because it trips up so many claimants. People who pay inflated invoices, overcharges, or disputed fees without raising a formal objection often find later that they have waived the right to recover. If you think a payment is unjust, documenting your objection at the moment you pay it matters far more than most people expect.

1
FindLaw. Mandarin Trading Ltd v. Wildenstein
2
Office of the New York State Attorney General. Brief of State of New York as Amicus Curiae in Support of Plaintiff-Appellant Paul Sperry
3
New York Courts. Georgia Malone and Co Inc v Rieder
4
New York Courts. Mandarin Trading Ltd v Wildenstein
5
New York State Senate. New York Code CVP Article 2 – 213
6
New York State Senate. New York Code CVP – 5001 Interest to Verdict, Report or Decision
7
New York State Senate. New York Civil Practice Law and Rules CVP 5004 – Rate of Interest