United Airlines Flights from London to San Francisco

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At the moment, you can catch a direct flight from London to San Francisco with the following airlines, including: Virgin Atlantic United Airlines British Airways Lufthansa American Airlines Selected airlines are based on historical data collected from flight bookings users made on Trip.com within the last 90 days.

It takes about 11 hours 7 minutes to fly from London (LON) to San Francisco (SFO).

By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from London to San Francisco is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.

Based on Trip.com data in the past 4 weeks, there is 47 flight per week flying from London to San Francisco. You can check the weekly schedule for popular airlines on this route below: Brussels Airlines: S/M/T/W/T/F/S -- SN9101 (12:45) Aer Lingus: S/M/T/W/T/F/S -- EI8987 (15:14)

To find best deals on flights from London to San Francisco, you can use various tools on Trip.com:
· Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on {{25a2b5_owDate}}, with one-way flights priced at just {{25a2b5_owPrice}}.
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The cheapest months to fly from London to San Francisco is May, when demand for travel is lower.

After crunching the numbers on our September flight calendar, it's currently cheapest to fly from London to San Francisco on September 24, 2025 with Aer Lingus, with prices starting at €371.

You can land at any one of the following hubs in San Francisco, with Heathrow Airport to San Francisco International Airport (LHR-SFO) is by far the most common option on this route: San Francisco International Airport (SFO).

The time difference between San Francisco and London is 8h.

Tickets can only be changed or cancelled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.