London has 6 airports. There are various public transport links for traveling between the city and the airport.
For transfer, between London airports it is best to use direct inter airport bus service by National Express.
Heathrow – Gatwick 75 mins (£25)
Heathrow – Stansted 90 mins (£ 22.50)
Heathrow is Europe’s largest airport and the world’s busiest. The airport has 5 terminals with the 6th one on the cards.
Heathrow Express Rail - This service runs every 15 minutes to London Paddington. The journey time is 15 mins. The cost of the ticket is-one way £21 and return £34. It is the fastest way to reach the city. There are 4 non-stop trains per hour on this route.
Trains depart from Paddington between 5.10am and 11.25pm and return from Terminal 4 between 5.23am and 11.41pm and Terminal 5 between 5.07am and 11.42pm. There are three stations at Heathrow: Central (for Terminals 1, 2, and 3) and Terminal 4, and Terminal 5. Travelcards and Oyster cards are not valid on the Heathrow Express.
Heathrow Connect – This train takes the same route as the Heathrow Express but stops at five intermediate stations. The journey time is 25 minutes. This service is less frequent with trains operating every 30 minutes. The cost is £ 9.90 for a one-way ticket.
Trains depart from Paddington between 4.42am (5.12am on Sundays) and 11.03pm and return from Heathrow Central between 5.29am (6.13am on Sundays) and 12.06am. Passengers for Terminal 4 and Terminal 5 should use the free inter-terminal service from Heathrow Express. Oyster pay as you go and Travelcards are not valid between Hayes & Harlington and Heathrow on this service.
Tube between Heathrow Airport and Central London
Heathrow Airport has three stations on the Piccadilly Line: Heathrow Terminal 5, Heathrow Terminal 4 and Heathrow Terminals 1, 2, 3. All stations are in zone 6 (central London is zone 1.) London Underground is the cheapest way to travel to and from Heathrow but it takes a long time (about 1 hour ) to central London.
The Piccadilly Line connects all Heathrow terminals with frequent services to central London between 5am and 12.30am (Heathrow Terminal 4 station closes at 11.30pm Monday to Saturday and 11.15pm on Sunday.
The cost of the Underground – Piccadilly line with Oyster card - one way £5.00. This is the cheapest way to get to the city but time-consuming. It takes about an hour to get to Central London from the airport.
Taxis are easily available and one can find black cabs lined up outside all the terminals of Heathrow or one can request a cab from the approved taxi desks. The fare is metered and a trip to central London will cost around £ 45-60. It is advisable to take one if you are traveling with small children or have a lot of luggage. Extra charges for late night or weekend may apply. If you wish to use a mini cab, make certain it is authorized.
There is a very big bus station at Heathrow airport with many local bus services to the city center and the nearby suburbs.
RailAir coach services take you to nearby railway stations that are connected with the rest of the country.
A hotel shuttle bus service operated by Dot2Dot transfers passengers from each terminal to their hotels. Additionally, HotelHoppa buses connect each terminal with hotels in the Heathrow area.
Gatwick airport is the second busiest airport in London and the Gatwick Express train to London Paddington costs £20 for a 30 minutes journey while a roundtrip ticket costs £35. An advance purchase ticket from Gatwick to London Victoria costs only £5 each way.