How to transfer between Heathrow terminals

The only direct walking link between two terminals at Heathrow is the one between Terminal 2 and Terminal 3 in the central area. Terminal 4 sits south of the central runways, and Terminal 5 sits on the western edge; neither links to anything else on foot.

The walk between Terminal 2 and Terminal 3 runs at level minus one, through a covered underground walkway with travelators for most of the route. From the T2 arrivals or check-in level, take the lift or escalator down to level minus one, follow the signs for Terminal 3 along the pedestrian underpass past the entrance to the Heathrow Terminals 2 & 3 Underground station, then continue along the walkway up into T3. The full walking between Terminal 2 and Terminal 3 takes about 10 minutes at a normal pace, longer with heavy bags. The route is fully step-free with lifts at each level.

There is no airside walking link between any two terminals. Once you have cleared security at one terminal you stay airside until you board, and a flight from a different terminal needs the free coach or, exceptionally, a re-clear at the new terminal landside.

Three rail services connect Heathrow's stations and are free between the airport's own stops when you tap in and tap out within the airport. The Heathrow Terminals 2 & 3 station sits between T2 and T3 in the central area, Terminal 4 has its own station under the building, and Terminal 5 has its own station under the building. Tap with contactless or Oyster at the start of the journey and again at the destination station; the system reads the two taps as an intra-airport hop and takes no fare.

Heathrow Express does not stop at Terminal 4. A T4 transfer that begins on Heathrow Express ends with a change at the central T2/T3 station to the Elizabeth Line, Piccadilly Line, or the free Flight Connections coach. The Elizabeth Line T4 and T5 trains run on different east branches (T4 to Abbey Wood, T5 to Shenfield), so a direct Elizabeth Line T4 to T5 hop needs a change at the central T2/T3 station. The Piccadilly Line is the only direct train between T4 and T5, calling at Hatton Cross between the two.

The free intra-airport segment is built into the way the system charges. Tap in at one Heathrow station, ride the train to another Heathrow station, tap out, and the system treats the journey as a zero-fare internal move. The free travel does not extend to Hatton Cross outside the airport zone, with one exception: the Piccadilly Line treats Hatton Cross as inside the Heathrow free zone for tap in and tap out, so a Hatton-Cross-to-T5 hop is also free if both taps are inside the zone.

The free inter-terminal coach at Heathrow runs airside, between all four terminal buildings, for connecting passengers on a single ticket with through-checked bags. The service is signed throughout the airport with purple Flight Connections signs from each terminal's arrivals concourse. Buses run every 6 to 10 minutes, step-free, with hold and overhead space for cabin and small hold bags. There is no fare to pay.

The most common use is the free inter-terminal coach between Terminal 4 and the central area, where the coach is the airside alternative to the Elizabeth Line. It also runs the T2/T3 to T5 leg and the T4 to T5 leg, in both directions. The coach takes around 15 minutes between Terminal 4 and the T2/T3 area, around 10 to 15 minutes from the central area to T5, and around 20 to 25 minutes T4 to T5 because of the longer airside road route between them.

The coach is for airside-connecting passengers only. If your bags are not through-checked, or you are on two separate tickets, or you need to clear UK immigration before your onward flight, the coach is not available; the landside trains (Elizabeth Line, Piccadilly Line, Heathrow Express where it applies) are the route instead, and these are also free between Heathrow stations.

The handling of luggage is the question that determines which route you take between terminals. Two cases:

• Through-checked single ticket: the bag is tagged at the original airport to the final destination. You do not see it until you collect at the final airport. Stay airside, follow Flight Connections signs to the coach or to the rail platforms, and head to the onward gate. UK immigration is not entered.
• Separate tickets, or bag not through-checked: you clear UK immigration on the Heathrow arrival, collect the bag from the carousel, exit landside, re-check in for the onward flight at the new terminal, re-clear security, and head to the onward gate. The full sequence takes a minimum of three hours in normal conditions, longer at peak.

For shorter waits or layovers without an onward flight (a deliberate stopover in London, a long delay, an overnight in a hotel near the airport) the luggage storage at Heathrow facilities at every terminal hold bags from a few hours up to a month. Standard luggage rules for connecting passengers apply: hand-baggage size and weight limits on the onward carrier override the inbound carrier's rules, and prohibited items are the same airside throughout. The connection process itself, with minimum connection times by airline and through-bag rules, lives on the connecting flights at Heathrow page.

Inter-terminal passenger assistance covers every step from the arrival gate to the onward gate. Book it through your airline at least 48 hours before departure. Heathrow's mobility team meets you at the aircraft and stays with you through the transfer, using the Flight Connections coach or the trains as needed. The full process is on the reduced mobility page; the Heathrow mobility helpline is +44 20 8757 2700.

Inter-terminal moves at Heathrow are short on paper and slower in practice. The figures below cover door to door, including a normal arrival walk, the platform or coach wait, the ride, the walk into the destination terminal, and the airside security re-screen at the destination. Landside transfers add a fresh check-in (typically 60 to 90 minutes for a long-haul flight, 30 to 45 for a short-haul) on top of the move itself.

Allow the upper end of each range at peak (06:00 to 09:00, 17:00 to 19:00) and when bag drop opens for a long-haul wave at the destination terminal. The Heathrow airport map shows every station, walkway, and coach stop in one view, useful for orientation before you set off. The T5 transit train between the main T5 building and the airside satellite buildings T5B and T5C runs every 3 to 4 minutes and takes around 3 minutes; build that into a T5 transfer if your onward gate is in a satellite.