Expiration Date
The expiration date is the last trading day on which an options contract can be exercised or sold, after which the contract becomes void and worthless if not in the money.
Every options contract has a finite lifespan defined by its expiration date. For standard U.S. equity options on the CBOE and other national exchanges, contracts traditionally expired on the third Friday of each month. The industry has since expanded to weekly expirations (known as 'Weeklys'), which expire every Friday, and even daily or Monday/Wednesday expirations for the most liquid products such as SPY, QQQ, and SPX.
The Options Clearing Corporation sets the technical expiration as the Saturday following the third Friday (for standard monthly series), but the last trading day is that Friday. For contracts still in the money at expiration, the OCC uses an automatic exercise threshold — if a contract is at least $0.01 in the money, it is automatically exercised on behalf of the holder unless specific instructions to the contrary are given through the holder's broker. This automatic exercise rule prevents accidental forfeiture of valuable contracts.
Expiration date selection has major strategic implications. Short-dated options (one to seven days out) have very little time value and are dominated by gamma risk — small stock moves produce outsized percentage changes in premium. Longer-dated options, including LEAPS that extend one to three years out, carry substantial time value and behave more like stock proxies because delta dominates. Theta (time decay) accelerates as expiration approaches, which benefits sellers of near-term options but punishes buyers who have not seen a favorable move.
Traders who hold short option positions into expiration face 'pin risk' — the risk that a stock closes exactly at the strike price on expiration day, making it uncertain whether assignment will occur. A short call writer at the $50 strike who does not hold the underlying shares could face assignment over the weekend and find themselves short 100 shares on Monday morning. Most active traders close or roll their short positions before the final trading day to avoid this scenario.
Expiration cycles also affect strategy selection. Monthly options tend to have tighter bid-ask spreads and greater open interest than weekly contracts, making them more capital-efficient for complex multi-leg trades. Weekly options, however, allow precise event-driven positioning around earnings announcements, Federal Reserve meetings, and economic data releases.