Which Airlines Operate The Most International Flights To & From The US?

Unsurprisingly, many airlines offer extensive international flight schedules from the US. Looking at Cirium data for September 2024, the top 15 airlines account for 72% of all international flights, with each of these having more than 1,700 flights in the month. The top operator, United Airlines, has an incredible almost 20,000 monthly flights.

As you would expect, the top places are taken up by US-based airlines. But some international carriers are well up there, too. We take a quick look at the top 20 airlines in this guide. All data is from Cirium, an aviation analytics company, for September 2024,

United Airlines – operating the most flights

The three main legacy airlines (United Airlines, American Airlines, and Delta Air Lines) take the top three places. As the largest airlines in the world, this is not really a surprise. Of these, United Airlines takes the top place – at least for September. It has almost 20,000 flights scheduled that month (including outbound and inbound flights) offering a leading total of 3.6 million seats.

Photo: Vincenzo Pace | Simple Flying

Its busiest routes include the following. Interestingly, although it has by far the most flights and most seats on offer, it does not operate any of the top routes by frequency (its top route comes in only eight place).

• Chicago (ORD) to Toronto (YYZ): 202 one-way flights (in September)
• Newark (EWR) to London Heathrow (LHR): 180 flights
• Newark (EWR) to Toronto (YYZ) (LHR): 172 flights
• San Francisco (SFO) to Vancouver (YVR): 164 flights

Read more about United Airlines and routes

American Airlines – coming in a close second

American Airlines comes in just behind United Airlines for total number of flights and total seats in September (but Delta Air Lines jumps it for total ASMs). It remains the largest airline in the US for fleet size and workforce – United edges just ahead in destinations served and number of routes – and it is interesting to see American fall just behind on international routes here.

Its busiest scheduled international routes in September include the following:

• Miami (MIA) to Havana (HAV): 216 one-way flights (in September)
• Dallas Fort Worth (DFW) to Cancun (CUN): 172 flights
• Dallas Fort Worth (DFW) to Monterrey (MTY): 159 flights
• New York LaGuardia (LGA) to Toronto (YYZ): 146 flights

Delta Air Lines – third of the legacy carriers

Delta Air Lines comes in third of the legacy carriers. It sits well behind Delta and American with close to 14,000 flights. Interestingly, however, it comes in second place for ASMs, indicating that it operates generally longer international flights. It falls behind the other carriers for Canada and Mexico flights – the biggest contribution to its third place ranking.

Photo: Lukas Wunderlich | Shutterstock

Its main scheduled international routes in September include the following:

• Seattle (SEA) to Vancouver (HAV): 187 one-way flights (in September)
• New York LaGuardia (LGA) to Toronto (YYZ): 163 flights
• Atlanta (ATL) to Mexico City (MEX): 148 flights

Air Canada – fourth overall, and operates the highest frequency route

Unsurprising, Air Canada tops the list for the most flights of a non-US-based airline. It operates over 11,000 international flights – giving average daily one-way departures from the US of 190 (United in the top place has an average of 332). It operates the highest frequency (for September 2024) international route of any carrier – between New York LaGuardia (LGA) and Toronto (YYZ).

Photo: Vincenzo Pace | Simple Flying

Air Canada’s main international routes include:

• New York LaGuardia (LGA) to Toronto (YYZ): 328 one-way flights (in September)
• Newark (EWR) to Toronto (YYZ): 207 flights
• New York La Guardia (LGA) to Montreal (YUL): 203 flights
• Los Angeles (LAX) to Vancouver (YVR): 150 flights
• Los Angeles (LAX) to Toronto (YYZ): 150 flights

JetBlue, WestJet, and Volaris – all between 3000 and 6000 flights

One US airline, one Canadian airline, and one Mexican airline take up fifth, sixth, and seventh places.

JetBlue’s main international route is between New York JFK and Santiago Airport in the Dominican Republic (STI) – with 158 scheduled flights. Volaris follows this with 141 scheduled flights between Los Angeles (LAX) and Guadalajara (GDL).

Photo: Minh K Tran | Shutterstock

JetBlue is, of course, also a competitor on the lucrative New York to London route. With only 60 flights scheduled in September, it sits well behind other carriers.

British Airways – top airline outside the Americas

Of the many airlines serving the US from Europe, Asia, and elsewhere, British Airways leads with the most scheduled flights in September 2024. It has almost 2,800 flights to and from London Heathrow to US cities.

These are obviously all long-haul flights – and this shows when you consider ASMs. The airline comes fourth behind the three dominant carriers of United Airlines, American Airlines, and Delta Air Lines.

British Airways’ top route is between London Heathrow (LHR) and New York JFK, with 238 scheduled one-way flights. This is, in fact, the third busiest route of all airlines (behind Air Canada LaGuardia to Toronto and Porter Airlines Newark to Toronto City Airport). Other busiest BA routes include Los Angeles and Chicago (both with 90 scheduled flights) and Boston with 86 flights.

The Heathrow to JFK route is one of the busiest and most lucrative air routes globally – well served by several operators behind British Airways:

• Virgin Atlantic has 184 flights scheduled in September
• American Airlines has 120 flights
• JetBlue and Delta Air Lines each have 60 flights

The rest of the top international operators

Together, the top 15 airlines make up 72% of all international flights to and from the US. For completeness, these are the remaining airlines in the top 20 list – with the total number of scheduled flights for September: