Execution
Daily closeout
Also known as: session closeout, EOD lockout
A time-based trigger that flattens the account and disables trading at a configured Eastern Time each day.
Daily closeout locks the trading account at a configurable time — typically 16:59 ET — to prevent end-of-day chaos and the trades that traders later regret. When the time hits, any open positions are flattened (if combined with auto-flatten) and further trading is disabled until the next session.
End-of-day discipline is one of the hardest things to enforce manually. By the close, traders are tired, sometimes down, and prone to one-more-trade thinking. Daily closeout removes the decision.