You’ve read the rule. You understand it. Then the MBE gives you a fact pattern with a merchant, a signed letter, and no consideration — and suddenly you’re not sure what you’re looking at anymore. Option contracts and firm offers are tested constantly on the MBE, and they trip people up not because the rules are complicated, but because students blur the line between them. Let’s fix that.

Why Option Contracts and Firm Offers Get Confused

Both concepts do the same thing: they make an offer irrevocable. That’s where the similarity ends. The distinction between them is one of the most reliable things the MBE tests in the Contracts subject, and the examiners know exactly how to exploit the confusion.

Here’s the core tension: at common law, an offeror can revoke an offer at any time before acceptance — even if the offeror promised to keep it open. That promise to hold the offer open is unenforceable without consideration. So how do you lock an offer down? Two ways. Option contracts do it under common law. Firm offers do it under the UCC. The rules are different, the requirements are different, and the MBE will absolutely put both in front of you.

Option Contracts: The Common Law Route

An option contract is a promise to keep an offer open, supported by consideration. That’s the whole rule. But every word in that sentence matters.

First, consideration. You need it. The classic MBE scenario: a seller tells a buyer, “I’ll hold this offer open for 30 days.” The buyer does nothing in return. The seller revokes on day 15. Was the revocation valid? Yes. There was no consideration for the promise to hold the offer open, so no option contract was formed. The original offer was freely revocable.

Now change the facts: the buyer pays the seller $100 in exchange for the seller’s promise to hold the offer open for 30 days. Now you have an option contract. The seller cannot revoke. If the seller tries to revoke and the buyer accepts within the 30-day window, a contract is formed.

A few things worth knowing cold:

Nominal consideration is enough. Courts generally don’t police the adequacy of consideration. A dollar, a peppercorn — it can work. The MBE isn’t going to give you $1 and ask whether that’s “real” consideration. It’s enough.

The mailbox rule does not apply to option contracts. This is a classic trap. Under the standard mailbox rule, acceptance is effective upon dispatch. But for option contracts, acceptance is effective only upon receipt by the offeror. If you mail your acceptance on day 29 but it doesn’t arrive until day 31, you’re too late.

Death doesn’t kill an option. Normally, the death of either party terminates an offer. Option contracts are an exception — the irrevocability survives the offeror’s death. The MBE has tested this.

UCC Firm Offers: No Consideration Required

A firm offer under UCC Section 2-205 is the Code’s version of an irrevocable offer, and it operates completely differently from an option contract. The big headline: no consideration required.

But the UCC imposes its own conditions. All three must be met:

  1. The offeror must be a merchant — someone who deals in goods of the kind or holds themselves out as having special knowledge or skill relating to the goods involved.
  2. The offer must be in writing and signed by the merchant.
  3. The offer must give assurances that it will be held open.

When those three elements are present, the offer is irrevocable for the time stated, or — if no time is stated — for a reasonable time not to exceed three months.

That three-month cap is tested. The MBE might tell you a merchant signed a written firm offer promising to hold it open for six months. The offer is irrevocable only for three months. After that, it’s freely revocable.

One more wrinkle: if the firm offer appears on the offeree’s form (not the merchant’s own form), the merchant must separately sign the assurance clause. The MBE has used this to test whether a firm offer was actually created.

Spotting the Difference in MBE Fact Patterns

Here’s a quick way to sort through a fact pattern involving option contracts and firm offers on the MBE:

Ask: Are we dealing with goods? If yes, UCC applies. Look for a merchant, a signed writing, and assurances. If all three are there, you have a firm offer — no consideration needed.

Ask: Is this a non-goods contract? Real estate, services, employment — common law controls. For an irrevocable offer here, you need an option contract supported by consideration.

Ask: Was there consideration? If it’s a goods contract and you’re looking at an option contract analysis, consideration still works. You can have a common-law-style option contract within a UCC transaction. But if the question is whether a firm offer exists under 2-205, consideration is irrelevant.

Try this: A hardware wholesaler sends a signed letter to a retailer on January 1st stating, “We will sell you 500 units of product X at $10 per unit. This offer will remain open until April 1st.” The retailer pays nothing. On February 15th, the wholesaler tries to revoke.

Is the revocation valid? No. The wholesaler is a merchant dealing in goods. The offer is in writing, signed, and contains assurances it will remain open. That’s a firm offer under UCC 2-205. But here’s the catch — the stated time is three months (January 1 to April 1). That’s right at the statutory cap, so the full period is irrevocable. Revocation on February 15th is ineffective. A valid acceptance before April 1st forms a contract.

Now change the facts: the wholesaler promises to hold the offer open for six months. The firm offer is irrevocable for only three months. After that, the wholesaler can revoke.

The Partial Performance Wrinkle

Don’t forget a third category of irrevocable offers that shows up in the same neighborhood: unilateral contracts. Once the offeree has begun performance — not merely prepared to perform — the offer becomes irrevocable. The offeror must give the offeree a reasonable time to complete performance. Mere preparation doesn’t count. The MBE has tested this distinction carefully.

This isn’t an option contract or a firm offer, but it lives in the same conceptual space. When you see a fact pattern involving partial performance and revocation, think irrevocability — just from a different source.

What to Know About Detrimental Reliance Here

Detrimental reliance can also make an offer irrevocable, even without consideration and outside the UCC. If the offeree foreseeably and reasonably relies on an offer to their detriment before acceptance, courts may treat the offer as irrevocable under a promissory estoppel theory. This comes up most often in construction subcontractor cases — a general contractor relies on a subcontractor’s bid when submitting their own bid, and then the subcontractor tries to revoke. The MBE has tested this.

FlashTables on Irrevocable Offers

FlashTables is a set of professionally formatted two-column PDF rule tables covering all seven MBE subjects — 704 rules total, organized by the official NCBE Subject Matter Outline. The firm offer and option contract rules are laid out side-by-side in the Contracts tables, so you can see the elements of each in one clean comparison. Whether you’re a law student locking in black-letter law for a contracts final or a bar-taker drilling active recall in the final weeks before the MBE, having these rules formatted for fast review makes a real difference when the distinctions are this close together.

Key Takeaways: What to Memorize

Here’s what you need to walk into the MBE knowing cold on option contracts and firm offers:

These rules are compact, testable, and frequently appear in MBE questions that hinge on a single element. Know which doctrine you’re in, check the elements, and you’ll recognize the right answer before you finish reading the choices. You can browse all the Contracts rules at getflashtables.com.