Boswell v. Zephyr Lines, Inc., 414 Mass. 241 (1993); J.A. Sullivan Corp. v. Commonwealth, 397 Mass. 789 (1986); G.L. c. 260, §§ 2, 2A
Unjust enrichment and quantum meruit in Massachusetts — the claim you plead when there is no contract
A claim in Massachusetts trial courts · Last verified August 26, 2026
These are the claims a plaintiff pleads in the alternative, and they are among the most frequently filed theories in Massachusetts for exactly that reason: nearly every contract complaint carries one.
They also carry the doctrine's central limit. Quasi-contract fails where a valid contract governs the same subject. As Boswell v. Zephyr Lines, Inc., 414 Mass. 241, 250 (1993), puts it, recovery in quasi-contract "presupposes that no valid contract covers the subject matter of a dispute."
What the claim is
You gave someone work, goods or money. They kept the benefit and did not pay. There is no enforceable contract to sue on.
Where the right comes from
Common law — restitution, not contract. The court is not enforcing a promise; it is reversing an unjust gain.
What a plaintiff has to prove
Unjust enrichment:
- A benefit conferred on the defendant by the plaintiff;
- The defendant's appreciation or knowledge of the benefit; and
- Acceptance and retention of the benefit in circumstances that make it inequitable to keep it without paying.
Quantum meruit:
- Services rendered to the defendant, in good faith;
- With a reasonable expectation of payment;
- The defendant accepted the services, knowing payment was expected; and
- The reasonable value of what was provided.
The third element of unjust enrichment is the one courts decide. Massachusetts asks whether retention is inequitable, not merely whether the defendant came out ahead. A defendant who got a benefit they never sought, could not refuse, and did not want is often allowed to keep it.
The two theories are not the same claim
Quantum meruit measures the reasonable value of services you performed. It presupposes you did work.
Unjust enrichment reverses a windfall. It reaches money, property or benefits that were never services at all — a payment made by mistake, an improvement to land, a benefit conferred on a third party.
A contractor who finished half a job has a quantum meruit claim. Someone who wired money to the wrong account has an unjust enrichment claim and no quantum meruit claim at all.
How long you have to file
Three years or six, depending on what the claim most resembles. Massachusetts has no fixed period for quasi-contract. Courts look to the gist of the action and borrow:
- Six years under G.L. c. 260, § 2 where the claim is contract-like — services rendered under a failed agreement, a benefit conferred in a commercial dealing;
- Three years under G.L. c. 260, § 2A where it is tort-like — a claim premised on conversion, fraud, or a wrong to property.
The Supreme Judicial Court has not resolved this with a single rule, and the answer therefore depends on how the underlying facts are characterised. A plaintiff whose claim is close to the three-year line should expect the defendant to argue the tort characterisation, and should plead the facts that support the contract one.
What has to happen before you file
Nothing.
What the claim pays
The value of the benefit conferred, not the plaintiff's cost and not the plaintiff's lost profit. In quantum meruit that is the reasonable value of the services; in unjust enrichment it is the value of what the defendant retained.
Twelve percent interest, under G.L. c. 231, § 6C.
No attorney's fees, absent a statute. Where the retention was also unfair or deceptive in a business setting, chapter 93A is the route to fees.
No punitive damages. These are restitutionary claims, and Massachusetts does not attach multipliers to them.
Who can be sued
The person enriched — which is not always the person you dealt with. A subcontractor who improved an owner's property under a contract with a general contractor who never paid may reach the owner in unjust enrichment, subject to the express-contract bar and the owner's own payments.
The express-contract bar
This defeats more of these claims than anything else, and the rule is strict.
Where a valid, enforceable contract covers the same subject matter, quasi-contract is unavailable — Boswell, 414 Mass. at 250; J.A. Sullivan Corp. v. Commonwealth, 397 Mass. 789, 793 (1986). The reasoning is that the parties already allocated the risk, and restitution would rewrite their bargain.
Three consequences follow.
Pleading both is normal, and recovering on both is not. A plaintiff may plead contract and quasi-contract in the alternative under Rule 8. If the contract claim succeeds, the quasi-contract count falls away.
The bar applies to a contract between these parties. A contract between the defendant and someone else does not automatically bar a claim by a plaintiff who was not party to it.
An unenforceable contract does not bar it. That is the point of the doctrine. Where the agreement fails for indefiniteness, for the statute of frauds, or because it was never properly formed, restitution is exactly the remedy that remains.
Common defenses
- The express-contract bar — a valid agreement covers the subject.
- No benefit conferred, or none the defendant appreciated.
- Retention is not inequitable — the defendant paid someone else for the same work, or never sought the benefit.
- Officious intermeddling — a volunteer who confers a benefit nobody asked for cannot charge for it.
- Limitations, on whichever period the characterisation produces.
- Unclean hands, since these are equitable claims.
What people get wrong
A signed contract kills the claim. Plaintiffs plead unjust enrichment as a safety net and are surprised when the defendant's own contract defeats it. Where the contract is valid and covers the subject, this claim goes.
A benefit is not enough. Massachusetts requires that retention be inequitable, and a defendant who never asked for the benefit frequently keeps it.
The two theories measure different things. Quantum meruit values services; unjust enrichment reverses a gain.
The deadline is not fixed. Three years or six, depending on the gist of the claim — which is a real risk, not a technicality.
There are no fees and no multiplier here. If the conduct was unfair or deceptive, plead 93A.
Where it came from
Restitution entered the common law through the fiction of the "implied contract" — courts pretended a defendant had promised to pay for a benefit, because assumpsit was the writ available and there was no other way to get relief. The fiction did real work and left real confusion, which is why these claims are still called quasi-contract and still carry contract vocabulary for a doctrine that has nothing to do with agreement.
Massachusetts has kept the substance and shed most of the fiction. The modern question is plain — was the defendant enriched, and would keeping it be unjust — and the doctrine's main function now is as a gap-filler.
The unresolved limitations period is the last piece of the old confusion. Because the claim is neither contract nor tort, no legislature ever assigned it a period, and courts borrow one by asking what the claim resembles. That is an honest answer to an artificial question, and it leaves practitioners guessing on the facts near the line.
Common questions
How long do I have to sue for unjust enrichment in Massachusetts?
Three years or six, depending on whether the claim is more like a tort or more like a contract. No single period governs.
Can I sue for unjust enrichment if I have a contract?
Not for the same subject matter. Where a valid contract covers it, quasi-contract is barred — though you may plead both in the alternative.
What is the difference between quantum meruit and unjust enrichment?
Quantum meruit pays the reasonable value of services you performed. Unjust enrichment reverses a benefit the defendant unfairly retained, whether or not it involved services.
Can I recover attorney's fees?
No, unless a statute applies. Chapter 93A is the usual route where the conduct was unfair or deceptive.
What if the contract was never signed?
That is when this claim does its work. An unenforceable or unformed agreement does not bar restitution.
How is the amount measured?
By the value of the benefit to the defendant — the reasonable value of services, or the value of what was retained.