Each customer (legal person or natural person, through a futures company) who opens an account in China Financial Futures Exchange has only one account number (transaction code), which is allocated by the exchange when the customer opens an account for the first time.

If a customer, Zhang San, has opened a financial futures account in Company A (futures company), such as 123456, then when he opens an account in Company B (futures company) again, his financial futures account is still 123456, but this customer's capital accounts in Company A and Company B are different and are allocated to customers within the futures company.

If this customer trades stock index futures in company A and company B at the same time (unlike securities companies, futures can be done in different companies at the same time), then his position limit is calculated according to a customer account number.