The time when stock index futures stop running varies from region to region and market. For the Chinese mainland market, the stock index futures contract of CICC (China Financial Futures Exchange) runs normally during the trading period, and there is no fixed stop time. However, in the event of major market fluctuations or risk events, CICC may take measures, such as increasing the margin ratio and limiting the number of open positions, to reduce market risks.

Stock index futures in other markets around the world, such as S&P 500 index futures and Nasdaq 100 index futures in the United States, also operate normally during their respective trading hours. Trading hours are usually fixed on local trading days, such as 9:30 am to 4:00 pm (Eastern Time).

Please note that the opening and closing times of the stock index futures market may be adjusted with the changes of policies, holidays and other factors. I suggest you pay attention to the official announcements of relevant exchanges and get the latest information.