The Qatar Airways DIA Terminalis located at Denver International Airport (DIA), namely in the South Hall's Jeppesen Terminal. Allow three hours for check-in and security when you arrive for your international flight. You can check in online up to 24 hours before your trip. Although there isn't a specific lounge on Qatar Airlines, elite travelers can access partner lounges. For help with rebooking if you miss your flight, get in touch with Qatar Airways customer service.