What Were America’s Busiest Flights in January?

It might be January, but there are still millions of Americans taking to the skies. With vacationers seeking the winter sun and business travelers shuttling between major hubs, there’s little time for the nation’s airlines to hibernate. 

Yesterday we brought you the world’s busiest international routes. Today, we’re drilling down into the U.S. domestic market.

Using the latest data from analytics firm OAG, Skift can reveal the sky-high links that had the most capacity this month. The full top 10 ranking is below, but here’s a little more context for the top five routes in our countdown:

#5: Las Vegas to Los Angeles (261,334 seats)

A whopping seven different airlines fly between Las Vegas and L.A., which helps promote healthy competition for price-conscious passengers. In January, Southwest Airlines operated the most flights, followed by Delta, United and Spirit. American Airlines, Alaska, and JetBlue completed the line-up.

The popularity of both the origin and destination with leisure and business traffic ensures this route is a star performer throughout the year. With the Super Bowl coming in February and thousands expected to descend on Las Vegas, demand next month could be even higher.

#4: Denver to Phoenix (278,198 seats)

Denver’s busy connection to Phoenix is served by four passenger airlines. Once again, Southwest has the lion’s share of capacity, with United, Frontier, and American completing the set. While both cities are great destinations in their own right, Denver serves as a major transit hub for United, while the Arizona capital is a key gateway for American Airlines. These onward connections help channel travelers through the airports and keep the route performing more strongly than you might expect.

#3: Atlanta to Fort Lauderdale (279,749 seats)

Atlanta makes the first of two appearances in our top five, with a link to Florida’s Atlantic coast. A total of five airlines flew between the two cities in January 2024 – but there’s one that dwarfs its rivals. Delta Air Lines’ home and hub in Atlanta means it offers more than half of the air capacity on the route, with almost 150,000 seats.

Spirit, Southwest, JetBlue, and Frontier split the remainder between them. Fort Lauderdale’s enormous popularity as a departure point for Caribbean cruises adds to the numbers, especially during the winter months. 

#2: Honolulu to Kahului (287,518 seats)

A reminder of the huge importance of aviation to island communities, the second busiest U.S. domestic route is an intra-Hawaii service. Despite being one of the nation’s most important air links, only two scheduled carriers operate between the airports.

Hawaiian Airlines typically flies the Boeing 717 on the route, while Southwest operates the much larger Boeing 737 Max 8. Although Southwest flies half the number of flights as Hawaiian, its bigger planes mean it can offer 70% of its rival’s capacity. The figures come at a time when the state is trying to strike a balance between tourism and keeping residents happy.

#1: Atlanta to Orlando (298,782 seats)

The shuttle between the Georgia hub and its southern neighbor takes the top spot for January 2024. Although the route boasts almost 300,000 seats, once again there’s a dominant carrier at play. Delta offered more than 189,000 seats during the month; more than twice the number of its three direct competitors combined.

The Atlanta-based airline can bring domestic and international vacation-makers to Orlando while flying Floridians through Georgia to plug into its colossal global network. The data comes in the same week that it was announced that Orlando authorities are to trim millions from the city’s tourism marketing budget.

Here’s the Top 10 List of Busiest U.S. Domestic Routes:

N.b. OAG data is based on available seat capacity – not the number of passengers carried.