A boarding position of B57 on Southwest Airlines is generally considered "marginal" and is often the "danger zone" for those hoping to avoid a middle seat. On a standard 737-800 or MAX 8 (which have 175 seats), B57 means you are approximately the 117th person to board, following the A-group (60 people), family boarding, and "A-List" members who missed their window. By the time B57 is called, almost all window and aisle seats in the front half of the plane will be taken. However, you still have a very high chance—roughly 80%—of securing a window or aisle seat if you head directly to the last five rows of the aircraft. Most passengers stop at the first available seat, leaving the back of the plane relatively empty for the late B-group. If you are traveling as a couple, B57 almost guarantees you will not be able to sit together in a window-aisle configuration; one of you will likely end up in a middle seat. In 2026, if the flight is "Full," B57 is a strong candidate for a paid "Upgraded Boarding" (A1-A15) if you absolutely cannot tolerate a middle seat.