Triple Witching Day

Third Friday in March, June, September, and December whenOptions, Index Options, and Futures Contracts all expire simultaneously. At times there may be massive trades in index futures, options, and the underlying stocks by hedge strategists, arbitrageurs, and other investors, resulting in volatile markets on those days. In the past, all contracts expired in the same hour, but steps were taken so that contracts now expire at the open as well as the close of the day instead of all at once. Smaller-scale witching days occur in the other eight months, usually on the third Friday, when other options, index options, and futures contracts expire concurrently. See also Double Witching Day.