I have multiple trading accounts with different brokers, and one of them is Ameritrade.
What I know about PDT (Pattern Day Trader) and Ameritrade is that:
1) If the balance more than $25K to start the day and you have
margin enabled, you can trade as many times as you want in a day.
Depending on the broker, they will give you 3 to 4 times margin.
In other words, if you have $25K, you have trading allowance of
$75K to $100K.
2) If the day's starting balance is below $25K, then you are
subject to maximum of 3 round-trip trades within 5 consecutive
market open days.
If balance is below $25K, you will start to see restrictions in
opening 4th trade...unless you deposit more money to bring it above $25K or ... I believe until some of the closing transaction money settles.
3) And after 90 days of no more violation, I believe the account
automatically removes the PDT flag, allowing you to trade again
(but still less than 3 round-trip trades within 5 market days).
This is bit confusing, and its best to maintain at least $30K, but ideally about $40K to $50K, to have cushion.
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