Cheap flights from Boston to San Francisco from $239

If you aren’t able to travel during the month of January, then book flights to San Francisco from Boston during September instead. Flights to San Francisco in September, while not as cheap as those in January, still average around $500.

Fly from Boston Logan Intl to San Francisco for the best Boston Logan Intl - San Francisco flight prices

You are more likely to see cheaper flights to San Francisco from Boston when booking weeks ahead of your departure date. In general, you can expect to find flights to San Francisco for around $575 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 Boston for as low as $478 on momondo.

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

Historically, on average around 18% of flights between Boston and San Francisco have experienced a delay on any given week. The average delay length over the past 12 months has been 172 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. Thursday 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 14% of their flights experiencing any sort of delay.

47 flights are operational daily from Boston to San Francisco as of June 2026. The most popular departure time for this route is 07:00, with 51% of flights per day taking off at midday.

The number of flights available between Boston and San Francisco is 330 per week as of June 2026. The most frequent departure day is Wed, with 16% of weekly flights leaving on this day.