Cheap flights from Boston to London from $256

The cheapest month to fly to London from Boston is in January. Flight prices, which tend to average around $527, are often lower during this time because this is during the off-season. The month of February is another great option to travel to London, with average flight prices from Boston averaging around $541.

The cheapest day to depart from Boston to London is on a Sunday. Travelers who choose to depart for London on a Sunday will often find tickets for as low as $749. If your travel schedule is flexible, try to avoid departing on a Saturday because tickets tend to average around $782. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.

Flying to London from Boston in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $669 when looking at flights departing in the afternoon. Flights to London are more costly in the evening, with an average ticket price of $771. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Boston Logan Intl to London Heathrow for the best Boston Logan Intl - London flight prices

You are more likely to see cheaper flights to London from Boston when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around $709 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Boston for as low as $656 on momondo.

There are 4 cabin classes available to choose from on Boston to London flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

No. A direct flight is the cheapest option for a flight between Boston to London.

As of August 2026, prices for Boston to London flights are approximately 40% cheaper when compared to flights at the same time last year.

United Airlines, Delta, and KLM are the most popular carriers operating from Boston Logan Intl to London

British Airways, Delta and American Airlines are the top three most popular airlines that fly to London from Boston according to our data. British Airways is the first choice among our users, with 46% of people opting to fly with this airline when traveling to London. Keep in mind that there are 17 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

Historically, on average around 11% of flights between Boston and London have experienced a delay on any given week. The average delay length over the past 12 months has been 146 minutes.

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

Monday is statistically the day of the week which experiences the fewest number of delays on this flight route. Sunday has historically seen more delays on average compared to the rest of the week.

According to our data, American Airlines have had the least number of delays on this route over the last 12 months; with about 9% of their flights experiencing any sort of delay.

Reykjavik (KEF) was the most common stop: 62% of momondo users choosing 1-stop flights on this route connected there.

Flights via Shannon (SNN) offer the lowest average round-trip price of $463.

Flights connecting via Shannon (SNN) have the shortest average one-way travel time: 8h 50m.

Dublin (DUB) has the shortest average layover time for this route: 1h 28m.

The number of flights available between Boston and London is 39 per day as of August 2026. The most frequent departure time is 7:00PM, with 87% of daily flights leaving in the evening.

As of August 2026, there are 274 flights per week flying from Boston to London. The most common day of the week flights depart is Tue, with 15% of flights taking off on this day.