Examples of unenforceable contracts include agreements with no real exchange of value, deals built on an illegal purpose, contracts signed by a minor or someone who couldn’t understand them, agreements extracted through threats or fraud, grossly one-sided terms, and oral promises that the law requires in writing. Some of these are void from the start, meaning the law treats them as if they never existed. Others are voidable, meaning the wronged party can walk away but doesn’t have to. Knowing which category a bad contract falls into controls what you can do about it.
Agreements With Nothing Exchanged
Every enforceable contract needs consideration: something of value each side gives up in exchange for what they get. A one-way promise isn’t a contract. If your neighbor says “I’ll mow your lawn every Saturday” and you say “great, thanks,” no contract exists because your neighbor is getting nothing in return.
Consideration doesn’t have to be money. It can be a service, a physical item, or even a promise to refrain from doing something you’d otherwise be entitled to do. What matters is the bargain: a performance or return promise counts as consideration only when both sides bargain for it, meaning the person making the promise seeks it in exchange and the person receiving the promise gives it in exchange.1Harvard Law School. Restatement Second Contracts 71 – Consideration A gift promise, no matter how sincere, isn’t enforceable because nothing flows back to the giver.
Deals Built on an Illegal Purpose
An agreement that requires breaking the law is dead on arrival. Courts will not help you enforce it, whether the underlying act is a felony or a regulatory violation. A contract to sell stolen goods has no legal standing, no matter how carefully the terms are drafted.
This principle also catches agreements that look innocent on the surface but involve someone working without a legally required license. Hire a person to wire your home’s electrical system without the license your jurisdiction requires, and the contract for that work is generally void. The fallout cuts both ways. An unlicensed contractor who doesn’t get paid often can’t sue to collect, and in some states you can recover money you already paid. The severity varies by jurisdiction. Some states treat the unlicensed work as a misdemeanor; others apply a more flexible “substantial compliance” standard that may forgive minor licensing gaps.
Contracts Signed by Someone Without Capacity
Both parties need the legal ability to enter a contract. When one party lacks capacity, the contract is typically voidable: the person without capacity gets to decide whether to honor it or walk away, while the other party stays bound.
Minors
In most states, anyone under 18 can enter a contract but can also back out of it at any time during minority or within a reasonable period after turning 18. The other party has no matching right to cancel. A 16-year-old who signs a car loan can void the deal and return the car; the lender can’t void it just because they’re dealing with a minor.
Once you turn 18, the clock starts. You can formally confirm the contract, or you can lock it in by continuing to perform under it. Keeping the car and making payments after your birthday counts as implied ratification, permanently binding you to the deal. The major exception involves necessities like food, shelter, clothing, and basic medical care. A minor who receives necessities generally remains responsible for their reasonable cost, even after disaffirming the contract.
Mental Incapacity
A person who cannot understand the nature and consequences of an agreement lacks the capacity to be bound by it. This covers individuals with severe cognitive impairments like advanced dementia, or someone in an acute psychiatric episode, who sign contracts they cannot meaningfully comprehend. These agreements are voidable at the option of the incapacitated person or their legal representative, not the other party.
Contracts Signed Under Pressure or Deception
A valid contract requires genuine, voluntary agreement. When consent is coerced or tricked out of someone, the contract is voidable by the person who was pressured. Under the Restatement (Second) of Contracts, a contract is voidable if a party’s agreement was induced by an improper threat that left no reasonable alternative.2Harvard Law School. Restatement Second Contracts 175-176 – Duress
Physical and Economic Duress
Physical duress is the clearest case: threatening violence to force someone to sign a deed. Economic duress is subtler and more common in business disputes. A classic example: a supplier who knows you’re dependent on their parts threatens to cut off deliveries mid-production unless you agree to a steep price increase, leaving you no realistic option but to accept.
The line between hard-nosed negotiation and economic duress matters. Driving a tough bargain doesn’t qualify. The threat must be improper, and the victim must genuinely have no reasonable way to avoid it, like being unable to find an alternative supplier before a critical deadline.
Undue Influence
Undue influence involves exploiting a relationship of trust or dependency rather than making an explicit threat. It shows up most often between caregivers and elderly patients, attorneys and clients, or family members with unequal power. A caregiver who gradually persuades a dependent, isolated person to sign over assets is the textbook case.
Fraud and Misrepresentation
When one party lies about a material fact to get the other side to sign, the resulting contract is voidable. The lie must concern a material fact, not an opinion or sales puff like “this is the best car on the market.” The person making the statement must have known it was false or spoken recklessly. The statement must have been intended to induce the other party to sign, and that party must have actually relied on it. A seller who hides known structural damage and tells the buyer the foundation is solid has committed the kind of misrepresentation that lets the buyer void the sale.
Mistake
A contract can be voidable when the parties were operating under a fundamental misunderstanding at the time the deal was made. When both parties share the same false belief about a fact central to their bargain, the contract is voidable by the party who was harmed. In the famous example, a buyer and seller both believed a cow was barren, and the price reflected that. When the cow turned out to be pregnant and far more valuable, the court let the seller void the sale because both sides had been wrong about a fact that fundamentally changed what they were exchanging.
When only one party is mistaken, voiding the contract is harder. You generally need to show something more: that enforcing the deal would be unconscionable, that the other party knew or should have known about your mistake, or that the other party caused the error. A contractor who accidentally drops a zero off a bid can sometimes void the resulting contract, especially if the price was so far below competing bids that the hiring party should have realized something was wrong.
Grossly One-Sided Terms
Courts can refuse to enforce a contract, or strike individual clauses, when the terms are so one-sided they shock the conscience. Under the Uniform Commercial Code, a court that finds a contract unconscionable at the time it was made can throw out the entire agreement, enforce the rest while cutting the offending clause, or limit how that clause applies.3Legal Information Institute. UCC 2-302 – Unconscionable Contract or Clause UCC Section 2-302 applies specifically to sales of goods, but courts apply the same principle to other contracts under general common law.
Unconscionability has two components. Procedural unconscionability looks at how the deal was made: Were the terms buried in fine print? Was the weaker party pressured into signing with no chance to negotiate or consult a lawyer? Substantive unconscionability looks at what the terms actually say: Is the interest rate astronomically high? Does one party waive nearly all their legal rights while the other retains every advantage? A predatory loan with a triple-digit interest rate and penalty clauses that make it nearly impossible to pay off is the classic example. Courts are most likely to intervene when both procedural and substantive problems appear together.
Adhesion contracts, the standardized forms you encounter with phone carriers, software companies, and most consumer services, are not automatically unenforceable. The problem arises when a company buries harsh terms in pages of dense text no one realistically reads and offers no ability to negotiate. Courts are especially skeptical of browse-wrap agreements on websites, where terms sit on a separate page the user may never visit. When key provisions aren’t clearly disclosed and the customer had no meaningful choice, courts have struck those terms down.
Terms That Violate Public Policy
Even when a contract doesn’t involve outright illegal activity, courts will refuse to enforce terms that violate broader public policy. Two of the most common examples are liability waivers that reach too far and non-compete agreements that lock employees out of their field.
Overbroad Liability Waivers
Businesses routinely ask you to sign waivers before a gym workout, a skydiving session, or a home repair. These exculpatory clauses can be valid for ordinary negligence, but a majority of states refuse to enforce waivers that attempt to shield a party from gross negligence or intentional misconduct. A gym that asks you to waive claims from a normal workout injury is on defensible ground. A gym whose waiver purports to protect it from liability even if a staff member deliberately tampered with equipment is not.
Non-Compete Agreements
Non-compete clauses restrict an employee from working for a competitor or starting a competing business after leaving a job. These agreements aren’t automatically unenforceable, but they face heavy scrutiny. To hold up, a non-compete generally must protect a legitimate business interest like trade secrets or client relationships, and the restrictions on time, geography, and scope must be reasonable. An agreement that bars a junior marketing associate from working in any marketing role anywhere in the country for five years is the kind of overreach courts regularly strike down.
The legal picture here is fragmented. Four states ban non-competes entirely, and more than 30 others impose significant restrictions. In early 2026, the Federal Trade Commission formally removed its proposed nationwide non-compete ban from the Code of Federal Regulations, ending a two-year effort to prohibit these clauses at the federal level.4Federal Register. Revision of the Negative Option Rule, Withdrawal of the CARS Rule, Removal of the Non-Compete Rule The FTC still has authority to challenge specific non-competes it considers unfair on a case-by-case basis, particularly those targeting lower-level employees or agreements with exceptionally broad terms. For now, enforceability remains a state-by-state question.
Oral Deals That the Law Required in Writing
Plenty of oral contracts are perfectly valid. But the Statute of Frauds, adopted in every state, requires certain categories of agreements to be in writing and signed before a court will enforce them. For high-value or long-term deals, a written record prevents the kind of “he said, she said” disputes that plague oral agreements.
The categories that typically must be in writing include:
- Agreements to buy, sell, or transfer an interest in real estate.
- Agreements that by their terms cannot be completed within one year of being made.
- Sales of goods at $500 or more. Under the UCC, a contract for the sale of goods at or above this threshold requires a writing signed by the party you’re trying to hold to the deal.5Legal Information Institute. UCC 2-201 – Formal Requirements Statute of Frauds
- Promises to pay someone else’s debt. If you guarantee that you’ll cover another person’s obligation, that promise generally needs to be in writing.
An oral agreement to sell your car for $800 is a typical example. You and the buyer might both be acting in good faith, but without a signed writing you’d have difficulty enforcing it in court if the buyer backed out.
The writing requirement doesn’t mean ink on paper. Under federal law, an electronic signature or record cannot be denied legal effect just because it’s electronic. Signing through DocuSign or clicking “I Agree” on a purchase order can satisfy the Statute of Frauds, provided the consent is informed and voluntary. For consumer transactions, federal law adds another layer: the business must clearly disclose the consumer’s right to receive paper records and get affirmative consent before going fully electronic.6Office of the Law Revision Counsel. 15 US Code 7001 – General Rule of Validity
Void or Voidable, and What You Can Recover
The practical consequences depend on whether the contract is void or voidable. A void contract never had legal force. Neither party can enforce it, no matter what they want. A contract for an illegal purpose falls here. Neither side can sue for breach, and the only real option is to walk away.
A voidable contract is valid and enforceable until the protected party decides to cancel it. Contracts involving minors, fraud, duress, and mistake typically fall here. The protected party can choose to rescind or let the deal stand. Both sides remain bound until the protected party acts. Waiting too long or continuing to perform can amount to ratification, locking you into a deal you once had the right to escape.
When a contract is rescinded or declared unenforceable, courts generally try to return both parties to where they started. If you paid money or handed over property under an agreement that later falls apart, you can seek restitution to prevent the other side from keeping a benefit they have no right to. Full restoration isn’t always possible. If you’ve already consumed a service or damaged goods you received, the math gets complicated, and courts may limit recovery to what’s fair under the circumstances.
One bad clause doesn’t always sink the whole contract. Many agreements include a severability provision stating that if a court strikes one part, the rest survives. Courts honor these clauses routinely, trimming the offending term and letting the remaining provisions bind both parties. This is how an overly broad non-compete might get narrowed to a reasonable scope rather than voided entirely, leaving the rest of the employment agreement intact.