Southwest Airlines is based at Terminal 1 at Ronald Reagan Washington National Airport (DCA) for both arrival Southwest Airlines DCA Terminal and departure. All passengers must arrive at least 90 minutes prior to a domestic flight in order to check in and clear security. The ticket counter opens 120 minutes before the first departing flight of the day, and all checked bags must be processed at least 45 minutes prior to the flight. After check-in, proceed through security to your assigned gate in Terminal 1. Upon arrival, follow signs to the baggage claim area on Level 1 in order to claim your luggage. For international passengers, passengers clear customs and immigration before proceeding to baggage claim.