Restrictions on the use of the card _ account auxiliary bank card: the card _ auxiliary bank card is only used for fund access and fund transfer with the main fund account. If the amount of the corresponding bank card in the main fund account is insufficient, you can transfer the money of the corresponding bank card in the sub-fund account, that is, the card _ auxiliary bank card, by means of fund collection or fund transfer, and then conduct stock trading. You can't trade stocks directly through the auxiliary bank card account. However, auxiliary bank cards cannot be transferred one after another, and the transfer of funds between the main fund account and the auxiliary fund account is free.

1. After an investor successfully opens a stock account, the securities company will send the investor's securities account and fund account to the investor via SMS, among which there are certain differences between the securities account and fund account: First, the securities account refers to the account set up by the securities registration and settlement institution for investors to record the clearing and settlement business of funds and stocks, while the fund account is an account opened by the securities company for individuals to deposit funds and stocks. Second, the securities account is equivalent to the ID card, which is unique. A capital account is equivalent to a bank card. If you transfer to another securities company, its capital account will be different. Therefore, after the investor changes the securities company, the capital account will change, but the shareholder account will remain unchanged. Third, the capital account can only buy off-exchange funds, and the securities account can do all transactions listed on the exchange. In the daily trading process, investors usually log in to the fund account.

2. Steps of adding a bank card to a securities account: After the stock account is opened, firstly, the three-party depository agreement is brought to the bank counter for binding, and the customer provides the securities company code and business department code in the banking system. Second, in some banks, such as ABC and ICBC, they can be directly bound at the counter of securities companies. Third, in some securities companies, five bank cards can be bound at the same time, and banks can transfer money through the platform of securities companies, which can be free of handling fees, and local or off-site bank cards can be used.

3. Generally, a securities account can be associated with the third-party depository accounts of up to five banks, with one as the main fund account and the other four as the auxiliary fund accounts. The main fund account can be used for fund deposit and withdrawal, fund transfer with the auxiliary fund account, securities trading and clearing and settlement.