The eight-hour hop between London Heathrow and New York's JFK Airport was the busiest international airline route in and out of the UK in 2021. While passenger and flight numbers are down on the route, according to Cirium’s latest On-Time Performance Report, five airlines continue to duke it out for business between Heathrow and JFK.

Across the ten busiest international routes out of Heathrow this year, a total of 16,373 flights pushed back. Of that number, 2,415 flights took off for JFK. The second busiest route was Heathrow to Dublin, with 1,832 departures.

In 2021, just 406,060 international flights operated from the UK. This compares to 1,399,170 flights in pre-pandemic 2019. Heathrow was the busiest airport by a country mile, with a total of 78,820 flights recorded this year.

Five airlines compete for business on the Heathrow - JFK run, including British Airways, Virgin Atlantic, American Airlines, Delta Air Lines, and newcomer JetBlue. This is despite the US only reopening its borders to UK citizens in November.

Passenger & flight numbers still down out of the UK

According to OAG, the Heathrow - JFK route is the fourth busiest international route worldwide in December, with 222,890 seats available across the month. It might sound like a lot, but Cirium says international flights to and from the UK are down 71% compared to 2019.

While the number of flights on any route is subject to seasonal fluctuations and evolving demand, on Friday, December 30, a total of 15 nonstop flights will jet between London Heathrow and New York's JFK Airports.

British Airways has five scheduled flights, all operated by Boeing 777 aircraft. Virgin Atlantic has four Airbus A350 flights timetabled in. American Airlines has two Boeing 777 flights set to run to JFK. Delta Air Lines has two flights listed - one operated by an Airbus A350, the other by a Boeing 767. Finally, JetBlue has its daily A321neo flight running between Heathrow and JFK.

The other big US-based airline, United Airlines, operates their New York - London flights out of its Newark hub rather than JFK.

JetBlue shakes up the flagship transatlantic route

The flagship transatlantic Heathrow - JFK has long been dominated by legacy airlines who charge relatively high fares and battle it out for the lucrative corporate dollar. The route had its biggest shakeout in years when JetBlue started flying in August.

“The response on both sides of the Atlantic has been overwhelmingly positive," said Robyn Hayes, JetBlue's Chief Executive Officer recently. He also adds JetBlue's premium fares are around 50% below the industry-wide average on the route.

However, whether JetBlue's sole narrowbody flight can make significant inroads into the premium market already serviced by the multiple daily widebody flights offered by the long-established carriers remains to be seen.

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Only one UK top ten route not originating at Heathrow

Meanwhile, rounding out the ten busiest international routes out of London Heathrow this year is Heathrow to Amsterdam in the third spot with 1,787 outbound flights. Heathrow to Paris Charles de Gaulle was fourth place, with 1,652 departing flights.

Taking the fifth spot was Heathrow to Frankfurt with 1,639 one-way flights. In the sixth spot was Heathrow to Athens with 1,572 outbound flights. Coming in seventh was the Heathrow to Dubai route with 1,495 departing flights.

In eighth place was the Heathrow to Lisbon route with 1,443 departing flights. Locking in the ninth position was Heathrow to Madrid run with 1,333 one-way flights.

Finally, only one top ten international route out of the UK this year did not depart from Heathrow. In tenth place was the London Gatwick to Dublin route. This year, 1,205 flights took off from Gatwick, heading to Dublin.