The USA has over 3,300 non-stop domestic routes in September, with 610,000 flights – over 20,000 a day – and 73 million seats in all. This raises the question: what are the USA's top-15 domestic routes? We take a look.

The top-15 domestic routes in September

The 337-mile link between Los Angeles and San Francisco is the USA's leading domestic airport pair in September, as shown below. This is based on analyzing schedules supplied by carriers to Cirium, the aviation data company. No other route from the LA Basin to San Francisco Bay Area is on the list. Notice the presence of Seattle: it appears five times, the same as Los Angeles.

  1. Los Angeles to San Francisco: approximately 1,878 round-trip flights in September
  2. Honolulu to Kahului: 1,738
  3. Las Vegas to Los Angeles: 1,576
  4. Los Angeles to New York JFK: 1,480
  5. Denver to Phoenix: 1,344
  6. Los Angeles to Seattle: 1,341
  7. Chicago O'Hare to New York LaGuardia: 1,327
  8. Anchorage to Kenai: 1,307
  9. Denver to Salt Lake City: 1,282
  10. Los Angeles to Phoenix: 1,280
  11. Denver to Los Angeles: 1,274
  12. Denver to Seattle: 1,266
  13. Seattle to Spokane: 1,259
  14. Portland to Seattle: 1,228
  15. Anchorage to Seattle: 1,210
The USA's top-15 domestic markets in September 2021
These are the USA's top-15 domestic routes by total flights in September 2021. Of course, the results would be somewhat different if seats or available seat miles were looked at. Image: GCMap.

One route has entered the list

If September is compared with July, Chicago O'Hare to New York LaGuardia has entered the top-15 (now seventh), pushing O'Hare to Denver out of the list. Pre-pandemic, O'Hare to La Guardia was the country's second-largest domestic market, and next month it will be at just 56% of its pre-pandemic flights.

There is a long way to go. Indeed, of the top-15 airport pairs, O'Hare to LaGuardia has the longest road to recovery, even by this simple measure, as would be expected of a significant business market.

United A319

Two of the top-15 now have more flights

Unlike O'Hare-LaGuardia, the 59-mile link between Anchorage and Kenai has exceeded its pre-coronavirus flight volume (+13.6%), likewise Denver-Phoenix (+6.0%). This can be seen below. However, rising coronavirus cases, reflected in lower TSA throughout, along with operational and other issues at particular carriers, may mean the recovery is pushed back somewhat again.

  1. Anchorage to Kenai: 113.6% of September 2019 flights
  2. Denver to Phoenix: 106.0%
  3. Denver to Salt Lake City: 100.0%
  4. Denver to Seattle: 98.8%
  5. Anchorage to Seattle: 92.3%
  6. Los Angeles to Phoenix: 92.2%
  7. Denver to Los Angeles: 89.5%
  8. Seattle to Spokane: 84.6%
  9. Honolulu to Kahului: 82.6%
  10. Los Angeles to Seattle: 78.4%
  11. Los Angeles to San Francisco: 76.6%
  12. Las Vegas to Los Angeles: 69.9%
  13. Portland to Seattle: 69.1%
  14. Los Angeles to New York JFK: 68.6%
  15. Chicago O'Hare to New York LaGuardia: 56.4%
Alaska Airlines Embraer 175
Alaska's Chicago O'Hare to Portland is the world's ninth-longest RJ route on September 27th. Photo: Vincenzo Pace | Simple Flying.

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Los Angeles to San Francisco

Although it varies by day, there is an average of 31 outbound departures each day between California's two largest cities, although it rises to 36 on particular days. Six carriers serve the route: Alaska; Delta; United; American; JetBlue; and Southwest. JetBlue in October 2020 after closing Long Beach.

If flights are considered, Alaska is the dominant carrier; if seats and available seat miles are looked at, it's United. The reason is obvious: Alaska will now only use the 76-seat Embraer 175, a frequency-boosting machine whose economics means that it is well suited to such short sector lengths. In contrast, 85% of United's flights are by larger narrowbodies: the 179-seat B737-900, 179-seat B737 MAX 9, and the 150-seat A320.

Will you be flying any of these 15 routes? Let us know in the comments.