Over the course of 2024, 77.75 million passengers traveled between the United States and Europe, marking the highest number in recorded history. This figure represents a 7% rise from 2023 and a 3% increase over pre-pandemic levels in 2019, though it does not reflect changes in fares. The ten busiest routes, with New York JFK to London Heathrow leading the way, accounted for a significant portion of this traffic.
According to the US Department of Transportation T-100 data, 337 US-European airport pairs each hosted over 5,000 round-trip passengers. Among airlines, Delta Air Lines carried the most passengers with 11.40 million, trailed closely by United Airlines with 10.96 million, American Airlines with 8.38 million, British Airways with 7.63 million, and Lufthansa with 5.29 million. However, United is set to overtake Delta for the most available seats during the 2025 summer season.
Within these routes, London Heathrow featured prominently, appearing in seven out of the top ten US-European markets. Collectively, Heathrow's US operations accounted for 17.56 million passengers, more than double the traffic volume of its closest competitor, Paris CDG. In 2024, travel between New York JFK and London Heathrow alone reached 3.16 million passengers, with British Airways capturing the largest market share at 39%.