Quick answer
- Check the "operated by" line on your booking. The operating airline decides your terminal.
- Confirm in your airline's app, then cross-check on Heathrow's flight checker.
- Check again on the day.
- Wrong terminal? Free trains and buses link the terminals, but it costs time.
- Tell your driver your terminal.
Heathrow handled 84.5 million passengers and 81 airlines in 2025, according to its annual report, across four terminals. Arriving at the wrong one eats into the time you need for bag drop and security.
The quickest ways to check your terminal
1. Your booking confirmation
Retained UK law (Regulation 2111/2005, Article 11) requires sellers to name the operating airline at booking, and states that "passengers shall be informed at check-in". The "operated by" airline sets your terminal.
2. Your airline's app or website
Your airline has the final say. Civil Aviation Authority guidance says passengers must be told of any change of operating airline as soon as it is known, so check again close to departure.
3. Heathrow's flight checker
Search your flight number on heathrow.com. Treat it as a cross-check: Heathrow's flight pages state that it does not verify the accuracy or completeness of the information shown.
4. Departure boards
At the airport, find your flight number on the screens before you queue.
Why the airline name is not enough
British Airways flies from both Terminal 3 and Terminal 5. Heathrow's terminal finder lists 12 BA routes that changed terminal in March and April 2026, five moving from Terminal 5 to Terminal 3 and seven the other way. Always check by flight number.
Schedules shift constantly: aviation data firm OAG handled around 126,000 schedule changes a day worldwide in 2019.
The codeshare trap
On a codeshare, one airline sells the seat and another flies it. If you book with Finnair but British Airways operates the flight, you head to BA's terminal, not Finnair's Terminal 3.
What to do if you go to the wrong terminal
Travel between terminals is free on Heathrow Express, the Elizabeth line and the Piccadilly line, if you only travel between terminals, Heathrow says. Use Oyster, contactless or a free ticket from station machines.
Heathrow's free travel map shows:
- Trains every 15 minutes from Terminals 2 and 3 to Terminal 4.
- Trains at least every 15 minutes from Terminals 2 and 3 to Terminal 5.
- Between Terminals 4 and 5: change at Terminals 2 and 3 by rail, or take the free H30 bus, every 20 minutes.
How long does it take?
As a benchmark, Virgin Atlantic advises connecting passengers to allow 90 minutes when changing terminals, against 60 within one terminal. Inside Terminal 5, British Airways says reaching the B and C gates takes about 20 minutes.
If you came by car
Every vehicle entering a terminal drop-off area pays £7, including taxis and private hire vehicles, and each re-entry is charged again, Heathrow says. Driving round to the right terminal means paying twice.
Why your driver needs the right terminal
Most passengers reach Heathrow by road: 46.3% used public transport in 2025, according to Heathrow's annual report. Give your terminal when you book, recheck it on the day, and tell your driver if it changes.
Flying from Heathrow soon? Book a GM Rides Heathrow transfer and include your flight number and terminal with your booking, so your driver heads for the right drop-off.
FAQ
Which terminal does British Airways use at Heathrow?
Terminals 3 and 5. Routes moved in 2026, so check your flight number.
Is it free to travel between Heathrow terminals?
Yes. Trains and the H30 bus are free if you only travel between terminals.
What if my terminal changes after I book?
Your airline should tell you about a change of operating airline as soon as it is known. Check its app on the day and update your driver.
