Terminal  at St. Louis Lambert International Airport (STL) is where United Airlines is located. The ticketing, customer service, and check-in counters for United are located in this terminal. This terminal also houses United's lounge for your convenience. United Airlines At STL Terminal because STL can get crowded during peak travel hours, if you're leaving on a United airline, make sure you get there early to get through security and find your gate. The baggage claim areas in Terminal 1 are where the luggage from United Airlines planes is delivered upon arrival. Passengers can choose from a variety of culinary and shopping options at the station. Make sure to verify any last-minute changes to your gate information and flight status.