Offer and acceptance analysis is a traditional approach in contract law used to determine whether an agreement exists between two parties. Agreement consists of an offer by an indication of one person (the "offeror") to another (the "offeree") of the offeror's willingness to enter into a contract on certain terms without further negotiations. A contract is said to come into existence when acceptance of an offer (agreement to the terms in it) has been communicated to the offeror by the offeree and there has been consideration bargained-for induced by promises or a promise and performance.

The offer and acceptance formula, developed in the 19th century, identifies a moment of formation when the parties are of one mind. This classical approach to contract formation has been weakened by developments in the law of estoppel, misleading conduct, misrepresentation and unjust enrichment.

Treitel defines an offer as "an expression of willingness to contract on certain terms, made with the intention that it shall become binding as soon as it is accepted by the person to whom it is addressed", the "offeree". An offer is a statement of the terms on which the offeror is willing to be bound. It is the present contractual intent to be bound by a contract with definite and certain terms communicated to the offeree.