AUSTIN (KXAN) — More than 15 million passengers flew out of Austin’s airport between January and September, new data from the airport shows.

New numbers from the month of September bring the year-to-date passenger total at Austin-Bergstrom International Airport to more than 15.5 million passengers.

This year now ranks as the third-busiest ever, with three months of data still to come. More than 17.3 million passengers were reported in 2019, which currently ranks as the airport’s busiest year on record.

This year, airport officials are projecting a total of 21 million passengers.

September 2022 ranks as the seventh-busiest month of all time. The top seven months have all occurred this year.

In September alone, 1,772,902 passengers were recorded. May remains the busiest month ever at AUS, with more than 2 million passengers.

September’s total is a 46.5% increase compared to September 2021, which saw a little more than 1.2 million passengers.

Southwest Airlines remains the largest airline operating at AUS in terms of passenger traffic. Almost four in 10 passengers in September traveled on a Southwest flight.

American Airlines is the second largest, with a quarter of all passengers flying with the airline. Delta Air Lines accounted for 11.7% of passengers at AUS and United Airlines flew about 10.5% of passengers. Alaska Airlines is a distant fifth, carrying 4.5% of passengers in September.

When looking at individual airlines, most saw year-over-year growth in September.

For the fourth month in a row, Allegiant Airlines saw the largest growth in passenger totals. In September 2022, the airline flew 28,217 passengers, up from 12,385 in September 2021 — a 128% increase.

Hawaiian Airlines increased its passenger totals by 107%, while both Southwest and American saw growth of more than 50%.

Some airlines saw lower passenger totals this September compared to last. Sun Country Airlines carried 149 this year, compared to 1,135 in September 2021, a decrease of 87%. Meanwhile, Frontier Airlines saw a 35% decrease in passenger traffic, and JetBlue Airways dropped by 13%.

Swift Air reported 164 passengers in September 2021 but none in September 2022.

Meanwhile, several airlines flew passengers in September 2022 but not in September 2021, due to COVID-related route cancellations. Air Canada and British Airways returned in October 2021.

Dutch airline KLM began its nonstop Austin-Amsterdam route on March 28, 2022. Meanwhile, German airline Lufthansa resumed its nonstop route to Frankfurt on April 8, after a two-year hiatus due to COVID. British airline Virgin Atlantic launched its nonstop route to London Heathrow on May 25.