Quote from loufah:
An explanation of how cash accounts in general interact with day trading is http://www.federalreserve.gov/BoardDocs/LegalInt/MarginRequirements/2003/20030512/.
my knowledge has fogged a bit cuz I don't deal w/ this much anymore, but here's hopefully an understandable explanation:
To put in simple terms, w/in a cash account, all purchases must be paid for before sold.
So if your account was flat, zero balance and you purchased a security then you're expected to deposit funds into your a/c by settlement date + 2 grace days prior to a first extention being filed on your behalf. if you chose to sell this stock on the same day you purchased it you'd fear a 90 day restriction cuz you sold the stock prior to fully paying for it, right? Wrong. As long as you pay for your purchase by settlement date you are okay cuz your a/c will have the funds for the purchase by the time the sell settles.
say your long x on monday (already settled and paid for) and you sell on tuesday. The sale settles on thursday. tuesday through wednesday your a/c has a credit balance from the sale proceeds. you can purchase a security on tuesday using this credit balance b/c by the time the purchase settles on thursday your credit balance will be a cash balance from the settling of the sell trade that occurs on the same day.
Simple rule of thumb to remember, you can't sell in a cash a/c what you have not paid for....exception as explained above, if your purchase is made using unsettled funds from a previous sale, you must wait for the previous sale to settle, thus paying in full your purchase before you can sell.
then there's the good faith violation which i can't remember. 3 good faith's in a 12 month rolling period is a 90 restriction. Again my memory is fuzzy so my example above might cause a good faith violation. Maybe a margin clerk can help me out on clearity.
A trade can always be entered for next day or same day cash settlement. I'm guessing most online firms require a phone call to the desk to get it entered. This of course shortens turn around time, but can also affect the execution price. A same day or next day settlement trade isn't reflected in the book if placed as a limit and a specialist or mkt mkr can take up to 10 pennies on the trade to get the oda done, per nfsc atleast...don't know if exchange rule.