If there is a loss, it is based on funds other than deposits in the account (the available funds in the account will be less and less, and the deposits will remain unchanged); On the other hand, if it is profitable, there will be more and more funds in the account and the deposit will remain unchanged. If the available funds in the account are zero (in many cases, it may not be completely zero), the futures company will inform the customer to add margin according to the debt-free system on the day of futures trading. If the customer fails to add the margin in time, the futures company can take the measures of compulsory liquidation at an "appropriate time" (the regulations of each futures company may be different).

In addition, futures trading is often calculated according to the settlement price.

(Many times "margin" is easily confused with "available funds", so it is good to distinguish it ideologically. )