Cheap flights from London to San Francisco from $685

If you aren’t able to travel during the month of February, then book flights to San Francisco from London during September instead. Flights to San Francisco in September, while not as cheap as those in February, still average around $812.

According to our data, Wednesday is the cheapest day to fly to San Francisco from London. The lowest ticket price found for a Wednesday departure recently was $947. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. When flying out on a Saturday, the most expensive travel day of the week, you can expect to see flight prices from London to San Francisco for around $2,141.

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 to San Francisco in the morning for as low as $885. 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 at midday when prices are $2,009 on average. Flights to San Francisco from London at midday 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 - San Francisco flight prices

You are more likely to see cheaper flights to San Francisco from London when booking weeks ahead of your departure date. In general, you can expect to find flights to San Francisco for around $963 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 for as low as $901 on momondo.

There are 2 cabin classes available to choose from on London to San Francisco flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

You could potentially save up to 41% on your flight if you consider stops on a London to San Francisco flight.

As of February 2026, prices for London to San Francisco flights are approximately 6% 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 147 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, Virgin Atlantic have had the fewest delays on this route over the last 12 months, with about 10% of their flights experiencing any sort of delay.

As of February 2026, there are 31 flights per day flying from London to San Francisco. The most common time of day flights depart is 11:00, with 58% of flights taking off at midday.

As of February 2026, 217 flights take off from London and land in San Francisco each week. The most common flight departure day for this route is Mon, with 14% of weekly flights taking off on this day.