If I am scheduled to depart from an airport for an afternoon or evening flight, what is the earliest the TSA will let me into the airport in the morning?
1 Answer
The only requirement is that the boarding pass must be "same day", so there is no real limit as to when you will be allowed through security as long as it's the same day as the departure.
The only exception to this would be a flight leaving shortly after midnight in which case you will be allowed through security the day before, although in this case it's possible you would be given some additional scrutiny by the TSA if you were to attempt to pass through security too far in advance.