What Is a Unilateral Contract?
A unilateral contract is an agreement in which one party promises to do something in exchange for the other party's actual performance — not for a return promise. The classic example is a reward offer: "I will pay $500 to whoever finds my lost dog." A contract forms only when someone actually performs the requested act, not when they promise to try.
Unilateral vs. Bilateral Contracts
- Unilateral — a promise exchanged for an act; acceptance happens by performing
- Bilateral — a promise exchanged for a promise; both sides commit up front
Most everyday contracts are bilateral. Unilateral contracts arise in rewards, prize offers, and certain insurance and option arrangements.
Key Principles
In a unilateral contract, the offeror generally cannot revoke once the other party has begun performance and is proceeding toward completion — revoking mid-performance would be unfair. The offeree, however, is never obligated to perform; they accept only by completing the act. Florida applies ordinary contract principles of offer, acceptance, and consideration to determine when such a contract becomes binding.
Related Terms
- Offer and Acceptance — How a unilateral contract forms by performance
- Consideration — The performance that supports the promise
- Offer — What invites performance
Barnes Walker
Barnes Walker's attorneys draft and litigate contracts of all kinds for Florida businesses and individuals. Request a legal inquiry for assistance.
Reviewed by the attorneys at Barnes Walker, Goethe, Shea & Robinson, PLLC