Six categories of contracts generally must be in writing to hold up in court: sales or transfers of real estate, agreements that cannot possibly be completed within one year, sales of goods worth $500 or more, promises to pay someone else’s debt, promises by an executor to cover estate debts out of personal funds, and agreements made in consideration of marriage. This rule, called the Statute of Frauds, exists in some form in every U.S. state. An oral deal in one of these categories isn’t automatically void, but if the other side walks away, a court usually won’t force them back.1British History Online. An Act for Prevention of Frauds and Perjuryes
One important thing to know up front: the writing requirement works as a defense. If you sue on an oral contract that should have been written, the other side can raise the Statute of Frauds and get your claim dismissed. If they don’t raise it, the court won’t step in on its own.
Real Estate and Interests in Land
Any contract to sell, transfer, or create an interest in real property needs to be in writing. That covers the obvious cases — buying and selling homes or land — and also mortgages, easements (the right to use someone else’s land for a specific purpose), and leases longer than a defined threshold. Most states draw the lease line at one year. A month-to-month rental can be oral, but a two-year apartment lease must be written.
Contracts That Can’t Be Completed Within a Year
If a contract is impossible to fully perform within one year from the day it’s made, it has to be in writing. The test is possibility, not probability, and this is where people get tripped up.
A promise to pay someone $10,000 exactly thirteen months from today must be written, because there’s no way to finish it within a year. A promise to pay $10,000 “within thirteen months” can be oral, because the money could be paid tomorrow. Even a lifetime employment contract is generally enforceable without writing, because the employee could die within the year and the contract would be complete.
Practically, this rule bites on employment agreements, service contracts, and supply deals with a fixed term over twelve months. A two-year consulting engagement needs to be in writing. An open-ended agreement with no defined end date usually doesn’t, because either party could theoretically wrap it up inside a year.
Sales of Goods Worth $500 or More
The Uniform Commercial Code requires a writing for any contract selling goods priced at $500 or more.2Legal Information Institute. Uniform Commercial Code 2-201 – Formal Requirements Statute of Frauds “Goods” means movable, tangible items: inventory, equipment, vehicles, materials. Services and real estate are governed by other rules. The writing doesn’t have to be a formal contract. It needs to show a deal was made, state a quantity, and be signed by the person you’re trying to hold to it.
Between merchants — businesses that regularly deal in the kind of goods being sold — there’s a shortcut. If one merchant sends a written confirmation of an oral deal and the other merchant receives it without objecting in writing within 10 days, the confirmation satisfies the writing requirement for both sides.2Legal Information Institute. Uniform Commercial Code 2-201 – Formal Requirements Statute of Frauds A merchant can’t stay quiet after receiving a confirmation and then invoke the Statute of Frauds when prices move.
When Delivery or Custom Work Covers the Gap
An oral goods contract is enforceable to the extent the goods have already been delivered and accepted, or payment has been made and accepted.2Legal Information Institute. Uniform Commercial Code 2-201 – Formal Requirements Statute of Frauds If you orally agreed to buy 100 units at $10 each and the seller delivered 40 that you accepted, the deal is enforceable for those 40 — but not the remaining 60.
Custom-made goods have their own exception. If items are specially manufactured for one buyer, can’t reasonably be resold elsewhere, and the seller has already started production or committed to procurement before the buyer backs out, the oral agreement is enforceable.
Promises to Pay Someone Else’s Debt
When you promise to cover another person’s debt if they default, that guarantee has to be in writing. Co-signing a loan is the clearest example: you’re agreeing to step in and pay if the primary borrower doesn’t. Because your liability only kicks in when someone else fails to pay, the law treats this as exactly the kind of secondary promise that needs documentation.
There’s an important carve-out called the main purpose rule. If you’re guaranteeing the debt primarily to benefit yourself economically, the oral promise may be enforceable without a writing. Telling a supplier “ship the materials to my subcontractor and I’ll pay if they don’t” might qualify, because you need the materials for your own project. The question is whether the promise is really about helping the debtor or advancing your own interests.
Executor Promises to Pay Estate Debts Personally
When an executor or administrator managing an estate personally promises a creditor to cover a shortfall from their own funds, that promise must be in writing. The logic matches the guarantee rule: the executor is taking on an obligation that isn’t originally theirs, and the writing requirement prevents creditors from pressing executors into oral commitments during a difficult period.
Agreements Made in Consideration of Marriage
An agreement where a marriage is the reason for one party’s promise must be in writing. Prenuptial agreements are the common example — contracts about how property will be divided if the marriage ends. A mutual promise to marry each other doesn’t fall into this category, but a property arrangement that only exists because the marriage is happening does. Prenups typically require both signatures, full financial disclosure, and time for each party to review and get legal advice. Specific procedural requirements vary by state, and agreements signed under pressure or without adequate disclosure get struck down regularly.
What the Writing Has to Look Like
The writing requirement is less formal than most people expect. A letter, an email, a receipt, or a series of text messages can satisfy it. Most states ask only for a memorandum showing that a deal was made, identifying the parties, describing the subject matter, stating the key terms, and bearing the signature of the person being held to the deal.
The signature doesn’t have to be handwritten at the bottom of a document. Initials, a stamp, a printed name, or any mark intended to authenticate can qualify. Only the signature of the party being charged matters. The person trying to enforce the deal doesn’t necessarily need to have signed anything themselves. Courts in many states will even piece together multiple documents, some signed and some not, as long as they clearly relate to the same transaction.
Electronic Signatures and Digital Records
Federal law gives electronic signatures and records the same legal weight as paper. Under the Electronic Signatures in Global and National Commerce Act, a contract or signature cannot be denied legal effect solely because it’s in electronic form.3Office of the Law Revision Counsel. 15 USC 7001 – General Rule of Validity Most states have adopted the Uniform Electronic Transactions Act, which carries the same principle at the state level. An email with a typed signature line, a DocuSign envelope, or a text thread with clear assent can satisfy the writing requirement.
Some documents stay outside this framework in most jurisdictions, including wills, trusts, and powers of attorney. Consumer transactions also carry additional procedural requirements before a business can rely on electronic records.3Office of the Law Revision Counsel. 15 USC 7001 – General Rule of Validity
When an Oral Contract Can Still Be Enforced
Even when a contract falls squarely within the Statute of Frauds, a few recognized exceptions can save an oral agreement.
Part Performance
This exception comes up most often with real estate. If someone has substantially acted on an oral agreement — taken possession, made payments, built improvements — a court may enforce the deal despite the missing writing. The actions have to be “unequivocally referable” to the oral agreement, meaning they only make sense if the deal existed. Someone who moved into a house, paid the owner monthly, and added a room has acted in ways hard to explain without a purchase agreement behind them.
Promissory Estoppel
When one person makes a promise, reasonably expects the other to rely on it, and the other does rely on it to their detriment, a court may enforce the promise even without a writing. The injured party has to show reasonable reliance, real harm, and that enforcement is the only way to avoid serious injustice. Courts don’t apply this casually, but it can rescue someone who quit a job, moved across the country, or spent significant money on the strength of an oral promise.
Judicial Admission
Under the UCC, if the party denying a goods contract admits in court — in pleadings, testimony, or under oath — that an oral contract existed, the Statute of Frauds defense falls away. Outside the UCC context, fewer states recognize this exception. The reasoning: the writing requirement is there to prevent fraud, and there’s no fraud to prevent once the deal has been admitted under oath.
Getting an agreement in writing before anyone performs is always cheaper than arguing over an exception later. A short email confirming the terms, signed off by both sides, is often enough.