The last expiration date of an option refers to the last date that the option contract must be fulfilled.

The final maturity date is usually sometime one month before the delivery date of the relevant futures contract. This allows the option seller to buy or sell related futures contracts when the buyer exercises the option to fulfill his obligations, and has a certain time to trade futures contracts in the futures market to hedge the liquidation, so that the option seller has the opportunity to avoid the situation that he may be unwilling or not prepared to make due delivery.

European options stipulate that Japanese can only exercise options when the contract expires. American options stipulate that options can be exercised on any trading day (including the contract expiration date) before the contract expiration date. The validity period of the same kind of option contract is different, which is divided into different time periods such as week, quarter, year and continuous month.