The Margin Used is equal to the position size multiplied by the Margin Requirement, summed up over all open positions. This amount is then converted into the currency of the account using the current midpoint rate. See the Margin Used Calculation Example below for an example on how to calculate your margin used.

In a margin account, the broker uses the $1,000 as security. If the investor's position worsens and his or her losses approach $1,000, the broker may initiate a margin call. When this occurs, the broker will usually instruct the investor to either deposit more money into the account or to close out the position to limit the risk to …