An option to purchase contract is an agreement in which a seller, for a fee, promises to keep an offer to sell open at a fixed price for a set period, while the buyer gets the right, but not the obligation, to go through with the purchase. Only the seller is bound. The buyer can exercise the option and buy, or let it expire and walk away, losing nothing beyond the fee already paid.
Why Only the Seller Is Bound
This is what contract law calls a unilateral contract. One party makes a promise; the other party’s role is to act on it or not. The Restatement (Second) of Contracts defines an option contract as “a promise which meets the requirements for the formation of a contract and limits the promisor’s power to revoke an offer.”1Legal Information Institute. Option Contract The seller (the optionor) commits to the price and the window. The buyer (the optionee) stays free.
The buyer pays something upfront, usually called the option fee or option premium. That payment is the consideration that makes the seller’s promise binding. It doesn’t obligate the buyer to close. It buys a guaranteed period during which the seller cannot revoke the offer, raise the price, or sell to anyone else. If the buyer never exercises, the seller keeps the fee and owes nothing more.
Because the seller carries all the risk of being locked in while the buyer stays flexible, option fees tend to reflect that imbalance. On a small residential property the fee might be a few hundred dollars. On commercial land with an option period running months or years, it can be a meaningful percentage of the purchase price.
What the Contract Must Contain
Consideration
Without consideration, an option is just a revocable offer the seller can pull off the table at any time. The fee is what converts it into a binding contract. Courts have long held that even nominal amounts, like one dollar, can qualify as valid consideration, provided the money is actually paid or tendered. A written acknowledgment that consideration was received, with no payment actually changing hands, creates only a rebuttable presumption and may not hold up if challenged.1Legal Information Institute. Option Contract
Definite Terms
The agreement has to spell out the essential terms clearly enough that a court could enforce them. That means a specific purchase price or a concrete formula for calculating it (such as the average of two independent appraisals), the length of the option period, and a description of the property that leaves no ambiguity about what is being sold. An agreement to negotiate the price later is generally unenforceable, because there is nothing definite for a court to order the parties to do.
Writing Requirement for Real Estate
Real estate option contracts must be in writing to satisfy the Statute of Frauds, which requires written agreements for any transaction involving the sale or transfer of land.2Legal Information Institute. Statute of Frauds An oral option to purchase real estate is almost certainly unenforceable, no matter how much money changed hands.
How the Buyer Exercises the Option
Exercising the option means formally notifying the seller that you are choosing to buy. The agreement will specify how notice must be delivered (written notice, certified mail, delivery to a particular address) and when it must arrive. These are not suggestions. Option deadlines are treated as hard cutoffs, and courts routinely hold that time is of the essence when an option contract sets an expiration date.
This is where most claims fall apart. A buyer who delivers notice one day late, by the wrong method, or to the wrong person may find the option has simply expired. There is generally no grace period and no court sympathy for a close miss, because the entire point of the contract is that the seller’s hands are tied for a specific, finite period. Extending that period by even a day would undermine the bargain.
Exercise usually requires more than sending notice. The buyer typically has to tender the purchase price or meet whatever other conditions the agreement specifies, such as providing proof of financing. Once the buyer properly exercises the option and satisfies those conditions, the unilateral option converts into a bilateral purchase agreement with mutual obligations. From that point on, both sides must perform or face breach-of-contract consequences.1Legal Information Institute. Option Contract
What Happens if the Option Expires
If the buyer doesn’t exercise before the deadline, the option dies. The seller is free to sell the property to anyone, at any price, with no further obligation to the buyer. The fee is gone; the seller keeps it as compensation for keeping the property off the market during the option period. Whether the fee can be credited toward the purchase price on exercise depends entirely on how the contract is written. Many do allow it, but it is not automatic.
The tax treatment of the fee depends on what happens with the option. For a buyer who lets it expire, the fee is treated as a capital loss, short-term or long-term depending on how long the option was held, with the holding period ending on the expiration date. For the seller, an expired option means the fee is reported as a short-term capital gain, regardless of how long the option period lasted.3Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses
If the buyer exercises instead, the math changes. The buyer adds the fee to the cost basis of the purchased property, and the seller adds it to the amount realized on the sale. Neither side reports the fee separately, because it becomes part of the overall transaction.
Protecting the Option Against a Later Buyer
An unrecorded option to purchase real estate is invisible to the outside world. If the seller turns around and sells the property to a third party who has no knowledge of your option, you may be left with nothing more than a breach-of-contract claim against the seller for damages. Recording a memorandum of the option in the county land records puts the world on constructive notice that someone else has a claim to the property. A prospective buyer who searches the title will see the recorded interest and know the property is encumbered.
Recording does not require filing the entire agreement. A short memorandum identifying the parties, the property, and the existence and duration of the option is enough in most jurisdictions. County recording fees vary, but the cost is minimal compared with the risk of losing the option entirely because a subsequent buyer recorded a deed first.
When the Seller Refuses to Honor a Properly Exercised Option
If you exercise correctly and the seller refuses to go through with the sale, you do not have to settle for getting your money back. Because every parcel of real estate is considered legally unique, courts can order specific performance, meaning the seller is forced to actually sell the property at the agreed price rather than simply paying damages. To get that remedy, you will need to show that the contract was valid, the terms were definite, you complied with every exercise requirement, and you were ready and able to close.
Specific performance is not available for every type of option. It is most reliably granted for real estate because no amount of money can replace a specific piece of land. For options on goods or other fungible assets, courts typically limit the remedy to money damages, since the buyer can go buy the same thing elsewhere.
How It Differs From Similar Agreements
An option to purchase is often confused with a right of first refusal, but they work in opposite directions. With an option, the buyer controls the timeline and can force a sale on the agreed terms whenever they choose during the option period. With a right of first refusal, the seller controls the timeline. The right-holder can only act when the seller independently decides to sell and receives a third-party offer, at which point the right-holder gets a chance to match it. Until the seller decides to sell, the right of first refusal sits dormant.
A lease-option is a different animal again. It combines a rental agreement with an option to purchase: the tenant occupies the property and pays rent, and a portion of that rent may be credited toward the purchase price if the tenant eventually buys. A standalone option to purchase does not involve occupancy. The buyer is simply paying for the right to buy at a future date. Lease-options are common in residential settings where a buyer needs time to build credit or save for a down payment, while standalone options appear more often in commercial real estate and land deals.