Margin is divided into trading margin and settlement reserve. Among them, the settlement reserve refers to the funds prepared in advance by the settlement members in the special settlement account of the exchange, which is the deposit not occupied by the contract. Trading margin is the margin that has been occupied by the contract. For example, if the margin ratio is 10% of the contract value, the first-hand contract value is1000000 yuan, and an investor deposits1000000 yuan in the margin account to engage in stock index futures trading, then the settlement reserve of the investor is1000000 yuan. If an investor buys a long contract one day, regardless of other expenses, the investor's margin account

The concepts of settlement guarantee and settlement reserve are completely different. As a common means to prevent default risk, settlement guarantee system is widely used in international markets such as Chicago Mercantile Exchange and Korea Exchange. CICC also draws lessons from international practices. Different from the current domestic commodity futures market, it requires some powerful institutions to settle directly with the exchange as settlement members, while other institutions without settlement ability cannot settle directly with the exchange, but with settlement members who have signed agreements. In this way, the membership structure of the exchange is pyramidal. In order to prevent the default risk of clearing members from spreading directly to the market, increase the financial resources of the market to resist risks, thereby enhancing the overall anti-risk ability of the market and protecting the fundamental interests of all market participants, CICC adopts the settlement guarantee system. CICC requires settlement members to pay the settlement deposit in cash according to the regulations of the exchange. In other words, the settlement guarantee is only collected by the exchange from the settlement members, and the settlement members may not collect the settlement guarantee from the trading members.