Pattern day trading rule
If you’re using a margin account AND it’s than $25,000 in value, you need to be aware of this rule. I use TD Ameritrade, but I imagine most are very similar, because it’s a FINRA rule (Financial Industry Regulatory Authority) that’s meant to protect us retail traders. Wikipedia says a Pattern Day Trader is someone who executes 4 or more day trades in 5 business days in a margin account (and the trades are more than 6% of their total …