Spirit said it would evaluate JetBlue’s proposal.
Spirit, Frontier and JetBlue are relatively small players at Hartsfield-Jackson International Airport, but each has sought to carve out a following in Atlanta in recent years.
In 2021, Spirit carried about 3% of passengers at Hartsfield-Jackson, Frontier controlled 2% of the market and JetBlue had less than 1%.
The Atlanta airport is dominated by Delta and its partners, which control more than 80% of the market. Southwest Airlines is in the No. 2 position with nearly 9%.
Even though Spirit controlled less than 3% of the market, that still makes it the third-largest carrier in Atlanta.
American Airlines carried 2.4% of the passengers in Atlanta, while United Airlines carried 1.4%.
Denver-based Frontier and Miramar, Fla.-based Spirit are known for their budget model, charging extra for large carry-on bags as well as checked luggage, and also charging for in-flight beverages.
JetBlue offers a different low-cost carrier model, with free snacks and drinks and more amenities.
When Frontier and Spirit announced their merger in February, they said the combined airline would “compete even more aggressively,” especially against the Big Four.
However, some Democratic lawmakers have raised antitrust concerns, saying they think the deal could reduce competition.
Frontier on Tuesday claimed a JetBlue-Spirit combination “would reduce competition and limit options for consumers” because of the two carriers’ “significant East Coast overlap.”
Frontier added that its proposed transaction with Spirit is “in the best interest of consumers and shareholders.”