Cheap flights from London Heathrow Airport to San Francisco from €504

The cheapest month to fly to San Francisco from London Heathrow Airport is in February. Flight prices, which tend to average around €486, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of February, then book flights to San Francisco from London Heathrow Airport during September instead. Flights to San Francisco in September, while not as cheap as those in February, still average around €502.

On average, the least expensive day to fly to San Francisco from London Heathrow Airport is on a Thursday. momondo users have found tickets for Thursday departures for as low as €675. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Saturday is the most expensive day to depart from London Heathrow Airport because it is more convenient for both business and leisure travellers. As a result, prices tend to be around €811.

According to our data, the cheapest time of day to fly to San Francisco is in the morning. momondo users have found flights departing from London Heathrow Airport to San Francisco in the morning for as low as €617. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. If you have a flexible travel schedule, then try to avoid flying in the afternoon when prices are €886 on average. Flights to San Francisco from London Heathrow Airport in the afternoon are generally more expensive because this time of day is more convenient for travellers’ schedules.

Fly from London Heathrow to San Francisco for the best London Heathrow - San Francisco flight prices

You are more likely to see cheaper flights to San Francisco from London Heathrow Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to San Francisco for around €600 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to San Francisco from London Heathrow Airport for as low as €531 on momondo.

You could potentially save up to 33% on your flight if you consider stops on a London Heathrow Airport to San Francisco flight.

As of May 2026, prices for London Heathrow Airport to San Francisco flights are approximately 8% cheaper when compared to flights at the same time last year.

Historically, on average around 12% of flights between London and San Francisco have experienced a delay on any given week. The average delay length over the past 12 months has been 145 minutes.

Generally, flights departing in the morning tend to experience fewer delays. Flights departing in the evening have, in the past, seen delays more frequently in comparison.

Tuesday is statistically the day of the week that experiences the fewest delays on this flight route. Wednesday has historically seen more delays on average compared to the rest of the week.

According to our data, United Airlines have had the fewest delays on this route over the last 12 months, with about 11% of their flights experiencing any sort of delay.

38 flights are operational daily from London Heathrow Airport to San Francisco as of May 2026. The most popular departure time for this route is 10:00, with 56% of flights per day taking off in the afternoon.

The number of flights available between London Heathrow Airport and San Francisco is 268 per week as of May 2026. The most frequent departure day is Mon, with 16% of weekly flights leaving on this day.