The dominant carrier at Hartsfield-Jackson is Atlanta-based Delta Air Lines, which makes up more than 80% of the market including its Delta Connection regional carrier flights.
The second-largest carrier at the Atlanta airport is Dallas-based Southwest Airlines, which has 9% of the market.
Even though Spirit controlled less than 3% of the market, that still makes it the third-largest carrier in Atlanta behind Delta/Delta Connection and Southwest.
American Airlines carried 2.37% of the passengers in Atlanta, while United Airlines carried 1.41%.
Frontier and Spirit say with the deal, they would go from the 7th- and 8th- largest airlines in the U.S. to the 5th-largest airline.
It’s yet to be seen how flights and service might change under a merged Frontier and Spirit. The airlines called their route networks “highly complementary” and said they planned to add new routes to “underserved communities” in the U.S., Latin America and the Caribbean.
They also said they expect to add 10,000 jobs by 2026. Spirit and Frontier had a combined $5.3 billion in annual revenues in 2021. Frontier’s majority shareholder, Indigo Partners, is a previous investor in Spirit.
However, some observers expect the deal could face antitrust challenges from the Biden administration, which has taken a more aggressive approach to challenging mergers, the New York Times reported.