What Terminal is United Airlines At BOS? United Airlines operates out of Terminal B at Boston Logan International Airport (BOS). Terminal B is one of the airport's main terminals, offering a wide range of amenities and services for passengers. United Airlines' check-in counters, security checkpoints, and boarding gates are all conveniently located within Terminal B. This terminal provides various dining options, retail stores, and comfortable waiting areas, ensuring a smooth and enjoyable travel experience for United Airlines passengers at BOS.