I just got approved for 4X buying power for day trading. This is the e-mail I received: ________________________________________________________________ This buying power may only be used intra-day and may not be held past market close. To receive day-trading margin, please respond to this email. Whether or not you choose to receive day-trading margin, when day-trading, it is your responsibility to track your start of day buying power. If your net day-trade purchases or sales exceed your start of day buying power, you will receive a margin call. Failure to meet this call promptly will result in your account being restricted to cash only (no margin) for 90 days. If you attempt to liquidate or buy to cover positions held overnight to raise next day-trading funds, the release of funds held for those positions will not impact your start of day buying power and any trades placed against those funds may result in a margin call. ________________________________________________________________ I'm confused as to what this means. Does this mean that I can't hold anything overnight past a certain percentage of my buying power? Let's say I have $100 cash and 4X buying power which is $400. I buy 4 shares of a $100 stock and sell all the shares throughout the day for the same price. I then repeat this action another 9 times. Will I receive a margin call even though I do not hold any positions overnight?