America's Global Reach
The US international air network funnels the majority of transoceanic traffic through just a handful of gateway cities — a concentration that has only intensified since COVID.
The Question
Which US airports handle the most international traffic? Which carriers dominate transatlantic, transpacific, and Latin American routes? And how has this network evolved over the past decade?
These questions matter for airline strategists planning international expansion, for airports competing to attract foreign carriers, and for analysts tracking the recovery of long-haul flying after COVID wiped out international traffic in 2020–2021.
The T-100 dataset — a full census of airline operations — gives us the answers. Unlike the sampled ticket data in DB1B, T-100 counts every passenger on every flight segment, making it ideal for measuring actual traffic flows on international routes.
Gateway Concentration: The Funnel Effect
The traffic/segments/breakdown endpoint with region=I filters to all international service. We take biennial June snapshots from 2015 to 2025 to track how the gateway hierarchy has shifted.
- Snapshot years:
- 2015, 2017, 2019, 2021, 2023, 2025
- Region:
- I (International — all sub-regions)
- Note:
- Results include foreign airports as origins (LHR, GDL, etc.) since the data covers all segments touching the US
The derived data filters to US airports only. T-100 counts both US and foreign-flag carrier operations, so JFK's total includes British Airways and other foreign carriers.
Top U.S. International Gateways — 2015 to 2025
Biennial June snapshots · T-100 scheduled international service · Passengers by origin airport
/traffic/segments/breakdown?by=origin®ion=I&service_class=FWhat the data shows: JFK and LAX are the top two international gateways throughout the decade. In June 2025, JFK handled 916,000 passengers and LAX handled 896,000. The gap to #3 (SFO at 449,000) is still enormous.
The hierarchy is mostly stable, but not static. The top group is usually JFK, LAX, SFO, MIA, and ORD, but the 2021 pandemic snapshot temporarily brought IAD into the top 5 while SFO dropped out. The bigger change is absolute scale: LAX grew from 713,000 in June 2015 to 896,000 in June 2025 (about +26%), while JFK grew from 901,000 to 916,000 (about +2%).
IAD (Washington Dulles) and BOS (Boston) have emerged as notable growers, reflecting increased European service. MIA’s position reflects its role as the primary Latin American gateway.
Carrier Landscape: Foreign Flag Leaders
Who actually flies these international routes? In these snapshots, the carrier breakdown is foreign-flag heavy and highlights where international passenger volume is concentrated.
- Snapshot years:
- 2015, 2017, 2019, 2021, 2023, 2025
- Scope:
- Top foreign-flag carriers in the international segment snapshots
These raw snapshots are dominated by foreign-flag operators, so this view is best interpreted as the foreign carrier landscape serving US international traffic.
Top International Carriers — 2015 to 2025
Biennial June snapshots · T-100 scheduled international service · Top carriers by passenger volume
/traffic/segments/breakdown?by=carrier®ion=I&service_class=FWhat the data shows: The carrier landscape in 2025 is strikingly foreign-carrier-heavy at the top. Volaris — a Mexican ULCC — is the single largest international carrier by passenger count (922,000 in June 2025), followed by British Airways (690,000) and Air Canada (588,000).
Foreign carrier diversity is broad: Turkish Airlines, Emirates, Qatar Airways, and Aer Lingus all appear in the top 15.
Top Routes by Region
The traffic/markets/breakdown endpoint with region filters (A=Atlantic, P=Pacific, L=Latin America) lets us see which specific city-pairs carry the most traffic. We compare 2015 and 2025 snapshots.
- Regions queried:
- A (Atlantic), P (Pacific), L (Latin America)
- Years:
- 2015, 2020, 2025
Markets data includes both directions of a route as separate entries (JFK→LHR and LHR→JFK). The derived data combines both directions into a single bidirectional passenger count.
Top International Routes by Region — 2015 vs 2025
June snapshots · T-100 scheduled service · Bidirectional passengers combined
/traffic/markets/breakdown?by=origin,destination®ion=A|P|L&service_class=FAtlantic routes are dominated by London Heathrow. JFK–LHR is the single busiest transatlantic route with 86,000+ bidirectional passengers in June 2025. DFW–LHR and ORD–LHR round out the top three — reflecting the concentration of transatlantic traffic through the legacy alliance hubs.
Pacific routes show a different pattern. The 2025 top routes are led by HND–LAX, LAX–SYD, and HND–HNL, with additional strength on ICN and Southeast Asia corridors such as SFO–SIN.
Latin American routes are heavily concentrated in US–Mexico and Caribbean flying. CUN–DFW and CUN–IAH lead in 2025, while routes like JFK–STI and JFK–SDQ show strong Caribbean demand.
What the Data Tells Us
Three structural observations emerge from the T-100 international data:
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Gateway concentration is persistent. A core group of JFK, LAX, SFO, MIA, and ORD dominates most snapshots, with a temporary 2021 reshuffle during the pandemic. New entrants like Austin, Nashville, and Raleigh are adding international routes, but their volumes remain marginal compared to JFK and LAX.
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Carrier diversity is increasing. The international market is far less US-dominated than domestic flying. Foreign flag carriers — particularly Gulf carriers, Turkish Airlines, and Mexican ULCCs — have grown substantially. Open Skies agreements and wide-body fleet expansion are structural drivers.
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Regional patterns differ fundamentally. Atlantic traffic concentrates on London. Pacific traffic spreads across Tokyo, Seoul, and emerging Southeast Asian cities. Latin traffic in these snapshots is overwhelmingly US–Mexico and Caribbean.
Every data point in this analysis comes from the AirStream API’s T-100 endpoints. The region filter (region=A|P|L|I) makes it straightforward to slice international traffic by geography, and the by=origin,destination breakdown reveals route-level patterns not visible in aggregate statistics.