Allegiant completes $1.5 B Sun Country merger, climbs to fifth‑largest U.S. airline

*TL;DR: Allegiant Air’s $1.5 billion acquisition of Sun Country Airlines lifts it to the fifth‑largest U.S. carrier by passenger volume.

Context Allegiant Air closed a deal first announced in October 2025, absorbing Sun Country Airlines into its operations. The transaction creates a fleet of 195 aircraft serving roughly 175 cities on more than 650 routes. Both brands will remain separate for the next 18 to 24 months while the Federal Aviation Administration reviews a single operating certificate.

Key Facts - The purchase price was $1.5 billion. - Combined passenger traffic now places Allegiant ahead of JetBlue and Alaska Airlines, making it the fifth‑largest U.S. airline. - CEO Gregory Anderson called the merger “a defining moment” and said it will produce a “more durable airline” that delivers lasting value to customers, employees, and shareholders. - Loyalty programs, credit‑card partnerships and existing flight schedules stay unchanged for the near term. - Cross‑booking between the two airlines is not yet possible. - After integration, the fleet is expected to grow to about 300 aircraft, incorporating Sun Country’s pending orders.

What It Means The merger expands Allegiant’s network reach, giving it a broader geographic footprint and a larger pool of aircraft to deploy on high‑demand routes. Maintaining separate brands during integration reduces immediate disruption for passengers while the companies align safety, maintenance and crew standards under a unified FAA certificate.

For investors, the deal signals confidence in Allegiant’s growth strategy and its ability to compete with larger legacy carriers. The combined scale should improve bargaining power with suppliers and airports, potentially lowering operating costs.

Customers can expect the same booking experience for now, but the eventual brand consolidation may bring new product offerings and a unified loyalty program. The airline’s next milestone will be FAA approval of the single operating certificate, a step that will determine when the Sun Country name is retired and the Allegiant brand fully absorbs the network.

What to watch next Monitor the FAA’s certification timeline and any adjustments to route schedules as the merged carrier moves toward a unified brand and expanded fleet.