If all reservable seats have been taken, there are a number of unreserved seats in coach C in Standard and coaches M or E in First Class. This means that if you don't have a seat reservation you'll still be able to travel in the unreserved part of the train.

On London North Eastern Railway (LNER) trains in 2026, there is no longer a dedicated "unreserved coach" for every journey; instead, unreserved seating is limited and distributed across specific coaches. For passengers in Standard Class, unreserved seats are typically found in Coach C. In First Class, unreserved seats are generally located in Coaches E or M. These seats are available on a "first-come, first-served" basis and are often the best option for those traveling with "Anytime" or "Off-Peak" tickets who have not made a pre-journey booking. LNER uses an "Electronic Seat Reservation" system (the digital displays above each seat) to show which seats are free for the entire journey or just for certain segments. If a seat is unreserved, the display will usually be blank or say "Available." To ensure a seat, LNER strongly encourages passengers to use their "Seat Sure" tool on the LNER app, which allows you to reserve a seat for free even just minutes before boarding. If Coach C is full, passengers are allowed to stand in the vestibule areas, but the "pro-tip" for 2026 travelers is to head straight to Coach C as soon as the platform is announced for the best chance of finding an open spot.