Walking is only available between terminals 2 and 3 as they are located at the centre of Heathrow airport while the other terminals are significantly farther apart.

Whether you can walk to Terminal 2 at London Heathrow depends entirely on where you are starting your journey. Terminals 2 and 3 are situated close together in the "Central Terminal Area" and are easily connected by a well-signed underground pedestrian walkway that takes about 10 minutes to traverse. However, if you are arriving at Terminal 4 or Terminal 5, you cannot walk to Terminal 2 due to the vast distances and the complex layout of the runways and taxiways. To travel between Terminal 2/3 and Terminals 4 or 5, you must use the free inter-terminal transfer services. This includes the Heathrow Express or Elizabeth Line trains, which are free for travel between terminals (you just need to tap a contactless card or Oyster card, but no charge is applied), or the underground Tube. There are also frequent shuttle buses. If you are arriving from outside the airport, Terminal 2 is easily accessible on foot from the Heathrow Central bus station and the associated car parks. Always allow at least 20 to 30 minutes for transferring between terminal buildings to account for waiting times and security.