London Heathrow LHR: the complete layover guide

Heathrow is really two airports in a trench coat: the Central Terminal Area with T2 and T3, then T4 and T5 standing alone at opposite ends of the field.

T2 handles most Star Alliance carriers. T3 takes a mix of long haul airlines including several oneworld carriers and Virgin Atlantic. T4 hosts SkyTeam and a long list of international airlines. T5 belongs to British Airways and Iberia. Between T2 and T3 you can walk in about 10 minutes through connecting corridors. Everything else means a ride.

Airside, follow the purple Flight Connections signage to the free transfer bus. It runs roughly every 10 minutes and the ride takes 15 to 20 minutes depending on tarmac traffic. The catch is what happens after the bus: Heathrow rescreens every connecting passenger at security, so the true terminal change costs 25 to 60 minutes door to door, and worse if a bank of long haul arrivals lands ahead of you.

Landside, the Elizabeth line and Heathrow Express link the terminal stations, and travel between Heathrow stops is free on these trains. That route only makes sense if you have cleared immigration and plan to re enter security from scratch.

Timing honesty: on a single ticket, treat 90 minutes as a sensible floor for any connection that changes terminals. On separate tickets you are checking in again from zero, so give yourself 3 hours minimum. People do make 60 minute connections here. People also sprint past you crying. Choose your camp.

If you are heading into London, three rail options leave from under the terminals. Heathrow Express is the fast one, about 15 minutes nonstop to Paddington and priced like it. The Elizabeth line takes roughly 30 to 40 minutes into central London for much less money and runs from all terminal stations. The Piccadilly line is the slow budget ride, around an hour to the center. For a layover dash, the Elizabeth line is usually the right balance of speed and cost.