Quadruple Witching

Quadruple witching is the name given to the third Friday of March, June, September, and December, when four different types of derivatives contracts all expire on the same day: stock index futures, stock index options, single stock options, and single stock futures. "Witching" is just market slang for expiration day, and "quadruple" refers to the fact that four separate contract types stop trading at once instead of expiring on their own schedules.

Most of these contracts normally expire monthly (stock and index options, for example, expire on the third Friday of every month), but futures contracts typically expire quarterly. Four times a year, the quarterly futures expirations line up with the monthly options expirations, so all four categories go dark on the same day. That overlap is what creates the "quadruple" effect, as opposed to "triple witching," where only three of the four line up, or "double witching," where only two do.

The nuance that trips people up is assuming quadruple witching automatically means a wild, chaotic trading day. It often brings noticeably heavier volume, because traders and institutions are closing out, rolling forward, or letting expire positions across all four contract types at once, and some of that activity clusters right at the closing bell (sometimes called the "witching hour"). But heavier volume is not the same as heavier volatility or a directional move; prices can settle in a fairly orderly way even on a high-volume witching day.

Another point of confusion is that quadruple witching is a calendar fact about contract expirations, not a prediction or a trading signal by itself. It matters because of the mechanical flows it creates (closing hedges, rebalancing index-tracking funds, arbitrage between the expiring derivative and the underlying stock), not because of any inherent market direction.