Spirit Airlines rejected a $400 million merger proposal from Frontier this week, saying the offer was financially inadequate and came too late. Spirit Airlines declined an opportunity to merge with rival low-cost airline Frontier on Wednesday.

IT issues at Frontier Airlines triggered a brief ground stop at all of the U.S. budget carrier's destinations on Thursday evening, according to an advisory from the U.S. Federal Aviation Administration.

Budget carrier Frontier Airlines announced on Wednesday that it has made another bid for fellow discount carrier Spirit Airlines, which is in bankruptcy, for an undisclosed sum.

A temporary Ground Stop was issued for all destinations for Frontier Airlines on Thursday, according to the Federal Aviation Authority.

Frontier Airlines is attempting for a second time to merge with the now bankrupt Spirit Airlines, which declared bankruptcy late last year as budget airlines struggle.

Rather than accept Frontier’s offer, Spirit said it will stick to its current plan to emerge from Chapter 11 bankruptcy.

Discount carrier says a merger would be a better path out of bankruptcy for Spirit, which has rebuffed the latest proposal.

Frontier and Spirit Airlines will once again try to merge, only months after the Biden administration won a key antitrust court battle to block

Spirit said almost immediately that it's not interested in the sale, and an attempted merger between the two airlines came to nothing in 2022

Spirit filed for Chapter 11 bankruptcy protection in November 2024, six months after a proposed merger with JetBlue collapsed.

Frontier and Spirit Airlines will once again try to merge, only months after the Biden administration won a key antitrust court battle to block an attempt by JetBlue to buy Spirit.