How far in advanced should I arrive at the airport before boarding?

2 hours minimum

During the holiday travel season 2 hours, but most of the time an hour and a half has been more than enough...

2 hours with no pre-check just over an hour with pre-check and a carry on.

2 hours before your flight.

I'd say 2 hours domestic. Look up airport or TSA for information. Luggage must be checked 45 minutes before flight at most airlines.

Couple hours. Worst case is you sit there waiting to board, as opposed to rushing around trying to get through security.

Depending on time of day and heavy holiday travel best to arrive 2 hours for domestic flights, 3 for international

Minimum 2 hours.