Margin is calculated at three periods during the day: the market's open, the market's close, and overnight. The Margin Requirements section shows your current margin, projected margin for the next period of margin calculation (Look Ahead) and the Overnight calculation (valid for futures only).
To view all Margin Requirements values, expand the section using the green plus (+) sign. To customize this view to show only the values you want to see, put a check next to these parameters and click the green minus (-) sign to contract the section.
Click to see how your margin requirements would be different if you had a portfolio margin account instead of a RegT margin account.
To help you stay on top of your margin requirements, we now provide pop-up messages and color-coded account information to notify you that you are approaching a serious margin deficiency. TWS will highlight the row whose value is in the distress state. The colors on your account screen tell you the following:
Yellow - You have only a 5% cushion above the margin requirement
Orange - Your margin cushion is depleted and you have a short time to enter into margin-reducing trades before your positions are liquidated. During this time you should be able to enter a trade that will decrease your margin requirement, but not increase.
Red - Your positions will shortly start to be liquidated as necessary to bring your account back within the margin limits.
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