Cheap flights from Philadelphia to London from £234

The cheapest month to fly to London from Philadelphia is in September. Flight prices, which tend to average around £486, are often lower during this time because this is during the off-season. The month of November is another great option to travel to London, with average flight prices from Philadelphia averaging around £499.

Our data shows that Tuesday is the least expensive day to fly to London. Tickets to fly out on this day can be as low as £505. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Philadelphia to London for around £746.

The cheapest time of day to fly to London is in the evening when flights can be purchased for as low as £595. Flights in the afternoon are often more expensive, with an average ticket price of £618.

Fly from Philadelphia to London Heathrow for the best Philadelphia - London flight prices

You are more likely to see cheaper flights to London from Philadelphia when booking weeks ahead of your departure date. In general, you can expect to find flights to London for around £622 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from Philadelphia for as low as £519 on momondo.

There are 3 cabin classes available to choose from on Philadelphia to London 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 22% on your flight if you consider stops on a Philadelphia to London flight.

As of March 2026, prices for Philadelphia to London flights are approximately 7% cheaper when compared to flights at the same time last year.

TAP AIR PORTUGAL, Icelandair, and British Airways are the most popular carriers operating from Philadelphia to London

Virgin Atlantic, British Airways and United Airlines are the top three most popular airlines that fly to London from Philadelphia according to our data. Virgin Atlantic is the first choice among our users, with 40% of people opting to fly with this airline when travelling to London. Keep in mind that there are 13 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.

Dublin (DUB) was the most common stop: 67% of momondo users choosing one-stop flights on this route connected there.

Flights via Dublin (DUB) offer the lowest average return price of £606.

Flights connecting via Dublin (DUB) have the shortest average one-way travel time: 9h 38m.

Dublin (DUB) has the shortest average stopover time for this route: 1h 33m.

As of March 2026, there are 4 flights per day flying from Philadelphia to London. The most common time of day flights depart is 19:00, with 100% of flights taking off in the evening.

As of March 2026, 33 flights take off from Philadelphia and land in London each week. The most common flight departure day for this route is Sat, with 45% of weekly flights taking off on this day.