Booking cheap flights to London

To get the best price, book your flight 3 to 5 months in advance and use a flexible date search tool like Google Flights. Avoid flying on weekends, as Tuesday and Wednesday departures are consistently cheaper for transatlantic routes.

1. Set up price tracking. Go to Google Flights, enter your departure city and London (LHR, LGW, or STN), and toggle the 'Track prices' button. You will receive an email alert whenever the price drops.
2. Use the flexible dates calendar. Instead of selecting specific dates, click on the calendar view in your flight search engine. Look for the cheapest dates highlighted in green to see if shifting your trip by 2-3 days saves you $200 or more.
3. Consider airport alternatives. While Heathrow (LHR) is the main hub, Gatwick (LGW) and Stansted (STN) often host budget carriers. Check the cost of the train transfer to central London—sometimes a cheaper flight to a further airport ends up costing the same once you add the train ticket.
4. Book directly with the airline. Once you find the cheapest fare via a search engine, navigate to the airline's official website to book. This ensures you have direct recourse if there is a cancellation or if you need to change your flight details.

Which London airport is best?

Heathrow is best for proximity to central London via the Elizabeth Line or Heathrow Express. Gatwick is fine if you take the Gatwick Express, but avoid Stansted or Luton if you are tight on time, as they are significantly further away.

Is it cheaper to buy a round-trip or two one-ways?

For international flights to London, a single round-trip ticket is almost always cheaper than booking two separate one-way tickets.