Expiry date

The end of a contract's defined life. Futures are written on a delivery month, and the exchange publishes the day on which trading in that month stops and the day on which it settles. A contract for difference written on a dated future inherits that calendar, so the instrument carries an expiry of its own; a contract written on a spot or cash market does not expire at all and remains open until it is closed or until the margin held against it fails its requirement.

At expiry a provider either closes remaining positions at a stated settlement price or rolls them into the following contract. A roll is two contracts, not one: the expiring position is closed and an equivalent position is opened in the next month, which trades at a different price. A cash adjustment is applied for that price difference so that the roll itself neither creates nor destroys value, and the rollover terms are published in advance rather than decided on the day.

Two dates get confused with it. The last trading day usually falls before the settlement day, so an instrument can stop being quoted while its expiry is still ahead. Separately, a pending order carries an expiry setting of its own, which governs how long an unexecuted instruction stays live, and has nothing to do with the life of the instrument it names. The first is a property of the contract, the second a property of the order.