A reasonable time for acceptance of an offer is however long an ordinary person in the offeree’s position would understand the offer to remain open, given the subject matter, the market, how the offer was sent, and any history between the parties. When an offer sets no deadline, it does not stay open indefinitely. It lapses automatically after that reasonable time, and any attempt to accept afterward is treated as a new offer rather than a binding acceptance.
The Rule Courts Apply
Restatement (Second) of Contracts § 41 is the starting point. An offeree’s power of acceptance ends at the time stated in the offer, or, if none is stated, at the end of a reasonable time. What qualifies as reasonable is a question of fact, which means a judge or jury decides it based on the specific circumstances rather than a fixed rule.1Open Casebook. Restatement (Second) of Contracts 41 – Lapse of Time The test is objective: what a reasonable person in the offeree’s shoes would have believed about how long the offer would last.
For sales of goods, the Uniform Commercial Code reinforces this. UCC § 2-206 says an offer invites acceptance “in any manner and by any medium reasonable in the circumstances” unless the offeror clearly specifies otherwise, and it allows an offeror who requested performance to treat the offer as lapsed if nothing happens within a reasonable time.2Legal Information Institute. Uniform Commercial Code 2-206 – Offer and Acceptance in Formation of Contract Both sources point the same direction. If you leave the deadline open, a court fills in the blank based on context, and that filled-in answer may not match what either party assumed.
What Shapes a Reasonable Time
Four factors do most of the work in setting the window: what is being sold, how volatile its price is, how the offer was communicated, and what the parties have done before.
The Subject Matter
The type of goods or services usually matters most. Perishable items compress the timeline sharply because the product is actively losing value. For fresh seafood or a load of strawberries, the reasonable time may be measured in hours, and waiting two days is almost certainly too late.3Business Law I – Interactive. 6.3 Duration of Offer Durable goods and real estate sit at the other end. An offer to sell a $500,000 generator or a commercial building does not degrade on the shelf, and both parties will expect time for financing, inspection, and legal review. Courts recognize that reality and often treat such offers as remaining open for days or weeks.
Market Volatility
A fast-moving price acts like a second clock. When the market for the item shifts quickly, the window shrinks, because allowing a delayed acceptance would let the offeree pocket a price swing at the offeror’s expense. For publicly traded securities, precious metals, crude oil, or agricultural futures, the reasonable time can be very short. An offer to sell gold at a quoted price loses its fairness as soon as the market moves. Stable goods work the other way. Standardized office supplies or consumer electronics at a set price do not shift much over several days, so courts allow more room.
How the Offer Was Communicated
The medium carries its own expectation about response speed. An offer made face to face or by phone generally lapses when the conversation ends unless the offeror says otherwise.1Open Casebook. Restatement (Second) of Contracts 41 – Lapse of Time Walk away without accepting and you cannot call back an hour later to claim the deal is still alive. Email and text messages signal a quicker back-and-forth than mail but do not demand an instantaneous reply the way a live conversation does, so a multi-week silence would usually be unreasonable. Postal mail builds in delay. The offeror is understood to accept that the letter needs time to arrive and a reply needs time to return, so the reasonable time stretches accordingly.3Business Law I – Interactive. 6.3 Duration of Offer
Prior Dealings and Industry Custom
If two parties have a track record, their past behavior sets the benchmark. A wholesaler and retailer who have exchanged orders for years on a ten-day cycle will be held to roughly that pace, and old invoices and email threads can prove it. A sudden demand for a 48-hour response after a decade of ten-day cycles looks unreasonable unless the change was clearly announced. Where no history exists, industry norms step in. Construction subcontractors routinely submit bids that general contractors rely on for weeks while awaiting project awards, and that expectation is strong enough that courts sometimes enforce it even without a written agreement. High-volume retail runs the other way, with offers often tied to a sale event or available stock. Reasonable is not abstract. It tracks how people in that specific business actually operate.
When the Clock Stops: The Mailbox Rule
Timing disputes often turn on when an acceptance becomes legally effective, not when it arrives. Under the mailbox rule, an acceptance is binding the moment the offeree sends it.4Legal Information Institute. Mailbox Rule If the offer is about to lapse and the offeree drops an acceptance in the mail on the last reasonable day, the contract forms at that moment, even if the letter takes several more days to arrive. Most jurisdictions apply the rule to email and fax as well, so long as the message is irrevocable once sent.
Two limits are worth knowing. The rule is a default, and an offeror can override it by stating that acceptance is effective only on receipt. And for option contracts, the rule flips: acceptance is not effective until the offeror actually receives it.4Legal Information Institute. Mailbox Rule The same letter mailed on the same day can form a contract instantly in one setting and accomplish nothing in the other.
Other Ways an Offer Dies Before Time Runs Out
Lapse of time is only one way an offer ends. Restatement § 36 identifies four main categories: rejection or counteroffer by the offeree, lapse of time, revocation by the offeror, and death or incapacity of either party. Any of these can cut short what would otherwise be a reasonable window.
Revocation by the Offeror
An offeror can generally revoke an offer at any point before acceptance, even after promising to keep it open, unless that promise is supported by consideration or fits a statutory exception. Revocation takes effect when the offeree receives it. It can also happen indirectly. Under Restatement § 43, the power of acceptance ends when the offeror takes definite action inconsistent with the offer and the offeree learns about it from a reliable source.5Open Casebook. Restatement (Second) of Contracts 43 – Indirect Communication of Revocation If someone offers to sell you their house and you then hear from the tenant that the owner just signed with another buyer, your offer is dead. A mere rumor does not count, and learning that the offeror received a higher competing offer does not terminate your power of acceptance, since the offeror may still intend to honor the original deal.
Counteroffer or Rejection
Making a counteroffer kills the original offer. Under Restatement § 39, an offeree’s power of acceptance is terminated by a counteroffer unless either party indicates otherwise.6Open Casebook. Contracts – R2K 39 – Counter-offers This trips people up. If a seller offers a car for $20,000 and you reply “I’ll pay $18,000,” you have not started a negotiation. You have destroyed the original offer. If the seller says no, you cannot circle back and accept at $20,000 unless the seller re-offers at that price. An outright rejection generally has the same effect, even if time remains on the clock. A few jurisdictions allow acceptance after a rejection as long as the original period has not expired, but that is the minority view.
Death or Incapacity
Under Restatement § 48, an offer terminates automatically if the offeror dies or becomes incapacitated, even if the offeree does not know about it. You cannot accept an offer from someone who has died, and ignorance of the death is no defense.
Keeping an Offer Open Past the Default
The reasonable-time default governs only when the parties have not locked the offer in place. Two mechanisms extend an offer’s life beyond what a court might otherwise allow.
Firm Offers Under the UCC
For sales of goods between merchants, UCC § 2-205 creates the firm offer. If a merchant signs a writing that explicitly promises to keep the offer open, it becomes irrevocable for the stated period, or for a reasonable time if none is stated, up to a maximum of three months. No consideration is required. If the assurance language appears on a form the offeree supplied, the offeror has to separately sign that specific term, which prevents irrevocability from being slipped into the fine print.7Legal Information Institute. Uniform Commercial Code 2-205 – Firm Offers
Option Contracts
Outside the UCC’s merchant setting, the common law requires consideration to make an offer irrevocable. Under Restatement § 87, an offer is binding as an option contract if it is in a signed writing, recites consideration for keeping the offer open, and proposes a fair exchange within a reasonable time.8Open Casebook. Restatement (Second) of Contracts 87 – Option Contract In practice this usually means the offeree pays the offeror something, even a nominal amount, in exchange for the hold. Real estate deals use this often, as when a buyer pays $1,000 for the right to purchase a property within 60 days.
Section 87(2) adds a second path. An offer that the offeror should reasonably expect will induce substantial reliance, and that does induce such reliance, can be enforced as an option contract to the extent necessary to prevent injustice.8Open Casebook. Restatement (Second) of Contracts 87 – Option Contract This is the principle that protects a general contractor who builds a project bid around a subcontractor’s quote. Pulling that quote at the last minute may be barred even without a formal option.
What Happens If You Accept Too Late
A late acceptance does not form a contract. Under the traditional counteroffer theory, an attempt to accept a lapsed offer works as a new offer from the original offeree back to the original offeror, who is then free to accept or reject it. The leverage flips. The party who held the power of acceptance is now the one making a proposal and waiting for an answer.
Some jurisdictions apply a waiver theory instead. If the original offeror receives a late acceptance and acts as if a contract exists, by shipping goods or beginning performance, that conduct may be treated as waiving the lateness. The practical point is simple. If you receive an offer you want, respond promptly. The longer you wait, the greater the risk that a court finds the offer has lapsed, and at that point your acceptance is only a request the other side is free to ignore.