3.7.11.3. Buying Power of Day-Trading Accounts
The minimum maintenance requirement for a day-trading account is 25%, the same as for the margin account of a trader holding a long position.
Equity over and above the minimum maintenance requirement for a day-trading account is called the maintenance margin excess. Day-trading accounts have a buying power of four times the maintenance margin excess. For example, if a day trader holds stock having a current market value of $600,000, his required maintenance margin is $150,000 ($600,000 / 4). If he has equity in his account o