Cheap flights from Boston to London from $345

The month of January is, on average, the cheapest month to fly to London Heathrow Airport from Boston, with most prices found around $526. If you’re not able to fly to London Heathrow Airport in January, then October is your next best option. Flight prices from Boston to London Heathrow Airport during October average around $535.

Our data shows that Wednesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $686. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $720.

According to our data, the cheapest time of day to fly to London Heathrow Airport is in the afternoon. momondo users have found flights departing from Boston to London Heathrow Airport in the afternoon for as low as $607. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the evening are often more expensive with an average ticket price of $714.

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

You are more likely to see cheaper flights to London Heathrow Airport from Boston when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $657 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from Boston for as low as $595 on momondo.

There are 4 cabin classes available to choose from on Boston to London Heathrow Airport 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 1% on your flight if you consider stops on a Boston to London Heathrow Airport flight.

As of June 2026, prices for Boston to London Heathrow Airport flights are approximately 3% cheaper when compared to flights at the same time last year.

KLM and Delta are the most popular carriers operating from Boston Logan Intl to London Heathrow

British Airways, Delta and American Airlines are the top three most popular airlines that fly to London Heathrow Airport from Boston according to our data. British Airways is the first choice among our users, with 48% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 16 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.

Historically, on average around 10% 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 144 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.

Saturday 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, Virgin Atlantic have had the least number of delays on this route over the last 12 months; with about 8% of their flights experiencing any sort of delay.

Reykjavik (KEF) was the most common stop: 55% of momondo users choosing 1-stop flights on this route connected there.

Flights via New York (JFK) offer the lowest average round-trip price of $1.

Flights connecting via Dublin (DUB) have the shortest average one-way travel time: 9h 00m.

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

The number of flights available between Boston and London Heathrow Airport is 30 per day as of June 2026. The most frequent departure time is 9:00PM, with 82% of daily flights leaving in the evening.

As of June 2026, there are 211 flights per week flying from Boston to London Heathrow Airport. The most common day of the week flights depart is Mon, with 17% of flights taking off on this day.