The average cost of an airline ticket out of Missoula International Airport has dropped nearly $40 over the past five years, a result of the city's growing list of destinations and the presence of discount carriers.

According to the Bureau of Transportation Services, the average cost of a ticket out of Missoula in 2013 was $452 – one of the costliest among the state's larger airports, behind only Kalispell and Helena, which had the highest average fares at $532.

But by 2016 and 2017, the average ticket price out of Missoula dropped substantially, making it the most affordable airport in the state. Helena remained the most expensive, the federal statistics suggest.

“We've added more competition to our market, and the more competition you have, the better your fares,” said Brian Ellestad, deputy director of the Missoula airport.

In 2016, the average full-year fare out of Missoula had fallen to $396. It increased slightly in 2017 to $418, though Missoula remained the most affordable airport in the state.

Ellestad said the difference in the two years can be attributed to Frontier Airlines and Missoula's average fourth-quarter fares. The average fourth-quarter fare in 2016 was $406, then in 2017 it jumped to $456.

“In 2016, Frontier ran its schedule all the way to Jan. 3, but in 2017 in the fourth quarter they pulled service in a lot of airports to restructure their routes,” Ellestad said. “It had a big impact on fares.”

This May, service out of Missoula will expand with a number of seasonal flights, including Delta's service to Atlanta and Frontier's service to Denver. United Airlines will launch service to Chicago, San Francisco and Los Angeles, and Allegiant will offer nonstop service to LA and Oakland.

Also in May, American Airlines will enter the Missoula market with seasonal service to Chicago and year-round service to Dallas/Fort Worth. Ellestad said that's likely to benefit Missoula travelers as well.

“American gives us more than just Dallas and Chicago,” Ellestad said. “It gives us connection opportunities to 130 destinations in their system. They file fares between point A and point B, which all the other airlines will match. It creates more competition and, generally, competition drives down airfares.”

Last year, according to the Bureau of Transportation Services, Missoula's average full-year fare of $418 was the lowest in the state, followed by Great Falls at $419, and Kalispell at $443. Bozeman was fourth at $457, followed by Billings at $461, Butte at $514 and Helena at $530.

“For an airport our size, we're happy with the number of nonstop destinations we have,” Ellestad said. “Moving forward, we'd like to switch some of our seasonal markets to year-round – Chicago and San Francisco – and get a second Portland flight. We'd like to get more frequency and extend the seasonal markets to year-round markets.”