Unilateral Offer

In one sentence

An offer that invites acceptance by performance of an act, rather than by a return promise.

Plain English

A unilateral offer is one where you say "If you do X, I'll pay you Y." The other person accepts not by promising to do it, but by actually doing it. For example, if you post a reward sign saying "$100 for the return of my lost dog," you're making a unilateral offer. Someone accepts by actually finding and returning your dog, not by promising to look for it. Unilateral offers are common in everyday life but can be tricky because acceptance happens through action, not words.

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Example

A company advertises "We will pay $1,000 to anyone who finds a bug in our software and reports it." A programmer finds a bug and reports it. The programmer has accepted the unilateral offer by performing the requested act, and the company must pay.

Used in a sentence

“The unilateral offer to pay a finder's fee was accepted when the employee located the missing documents and delivered them.”

Related terms

Mutual Assent

Both parties agree to the same contract terms at the same time.

Offeror

The person who makes an offer to enter into a contract.

Mirror Image Rule

The principle that an acceptance must match the offer exactly, or it becomes a counteroffer instead.

Performance

The act of doing what a contract requires, such as delivering goods or paying money.

Legal Value

Something of worth in the eyes of the law that can support a binding contract.

Capacity

The legal and mental ability to enter into a binding contract.

Offer

A proposal to enter into a binding agreement on specific terms.

Acceptance

Agreeing to the exact terms of an offer, creating a binding contract.

This page is a plain-English reference and is not legal advice. Laws vary by jurisdiction and change over time. For specific situations consult a licensed attorney.