The Busiest International Routes From The US In 2026

Cirium frequency data for 2026 shows the busiest international routes from the U.S. are dominated by Canada, with Toronto accounting for much of the top demand. Among the nine U.S.-origin city pairs with more than 3,000 annual frequencies, four connect to Canadian airports, totaling 23,463 departures. That adds up to 50.7% of the top nine pairs’ departures, surpassing Europe, Latin America and the Caribbean. The leading route by annual frequency is New York LaGuardia–Toronto (7,901), followed by New York JFK–London Heathrow (7,338). Toronto Pearson, especially, represents nearly half of the busiest international routes from the U.S.