DENVER (AP) — Frontier Airlines, which has struggled more than other U.S. carriers to recover from the pandemic, says it is eliminating change fees on some tickets and creating four fare classes to boost its appeal to more travelers.

The Denver-based airline said the changes taking effect Friday would make buying a ticket less complicated.

Frontier, like rivals Spirit Airlines and Allegiant Air, advertises low fares but tacks on more fees than the larger carriers. Consumers pick from a menu of extras that increase the final price they pay — often by a significant amount.

The budget carriers have struggled, however, as big airlines created their own no-frills tickets to lure away the most cost-conscious travelers.

Frontier is switching to four fare classes, which it calls basic, economy, premium and business. Those in “basic” will still have to pay extra for things like bringing a carry-on bag, selecting a particular seat and changing or canceling a reservation.

But change fees will be eliminated for passengers in the other three groups, who will also be able to buy extras such as seat selection and bringing a carry-on bag in bundles instead of singly.

Frontier also said it is bringing back phone support for customers within 24 hours of their flight.

CEO Barry Biffle called the announcement “the beginning of a new era for Frontier.”

Frontier has not earned a full-year profit since 2019, and it has lost about $400 million since then and failed in an attempt to merge with Spirit.

The company’s shares fell 2% on Friday.