Everyone knows the role of banks, but for stock index futures, some banks are more closely related, that is, settlement banks. The settlement bank refers to the bank designated by the exchange to assist the exchange in the settlement of futures transactions. In futures trading, due to the frequent exchange of funds, if the exchange and members' funds are not in the same bank, it will inevitably affect the efficiency of fund allocation. According to the regulations of the Exchange, the Exchange shall open special settlement accounts in all settlement banks to deposit members' deposits and related funds. Members need to open a special fund account in the settlement bank to deposit the deposit and related funds. The settlement of futures business funds between the exchange and its members shall be handled through the special settlement account of the exchange and the special fund account of the members, and barrier-free settlement shall be realized in this way.