Allegiant and Sun Country are officially one, large leisure airline

Leisure airlines Allegiant Air and Sun Country Airlines are now one — though each brand will live on.

Travelers can expect little immediate change following the roughly $1.5 billion merger that closed Wednesday. Both the Allegiant and Sun Country brands will continue to operate separately, including their Allegiant Allways Rewards and Sun Country Rewards loyalty programs, until they are combined under the Allegiant name in the next 18-24 months, or by May 2028.

The combination cements Allegiant's place as the eighth largest U.S. airline by seats, schedule data from aviation analytics firm Cirium shows.

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"Today marks a defining moment in Allegiant's history as we officially join forces with Sun Country to create the leading leisure-focused airline in the United States," said Gregory Anderson, CEO of Allegiant, in a statement. "With a combined fleet of 195 aircraft serving nearly 175 cities, we are expanding access to affordable, reliable, and convenient travel for the communities that have long been the foundation of our business, while offering customers broader reach and more destinations."

The Allegiant-Sun Country merger comes amid a flurry of merger talk in the U.S. United Airlines CEO Scott Kirby confirmed in April that he had approached American Airlines about a potential deal to create the world's largest airline. And JetBlue Airways is reportedly shopping itself around for a merger partner.

"Is there room for some mergers in the ​aviation industry? Yeah, I think there is," Transportation Secretary Sean Duffy told CNBC in April.

Airline merger chatter has quieted some since the collapse of Spirit Airlines on May 2. However, many industry insiders remain confident that any potential deal would need to occur in the next two-and-a-half years, or during the remaining term of President Trump.

In the meantime, airlines are quickly adding flights to fill the void left by Spirit's sudden shut down.

At Allegiant, Sun Country's former home at Minneapolis-St. Paul International Airport (MSP) is now the combined airlines's largest base by both flights and seats, Cirium schedules show. Harry Reid International Airport (LAS) in Las Vegas, the airline's headquarters, is the fifth largest.

The leisure airline now also includes Sun Country's air cargo operations for Amazon Prime Air and its charter business.

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