Four significant airlines now dominate the U.S. airline industry: American Airlines, Delta Air Lines, Southwest Airlines, and United Airlines. Eight big airline mergers since 2000 have reshaped the industry, with storied names like Continental Airlines, Northwest Airlines, and US Airways disappearing into other brands. Two more mergers are proposed: JetBlue Airways wants to buy Spirit Airlines for $3.8 billion, and Alaska Airlines has agreed to buy Hawaiian Airlines for $1.9 billion. These mergers have shaped the industry, with American Airlines, Delta, Southwest, and United now flying 78% of all seats in the U.S. market. Two more mergers are proposed, with JetBlue Airways attempting to block Spirit Airlines and Alaska Airlines agreeing to buy Hawaiian Airlines.

In 2011, Southwest and AirTran merged to form Southwest-AirTran, which would combine the largest U.S. airlines by seats. In 2013, US Airways and American merged to form American, which would be the market leader. In 2016, Alaska announced a deal to buy Virgin America, bringing together the country's sixth and 11th largest airlines. In 2022, JetBlue and Spirit merged to become the fifth-largest U.S. airline by seats. Alaska and Hawaiian recently announced a deal to buy Hawaiian for $1.9 billion, with the combined airline operating with two customer-facing brands. The merger is expected to close by June 2025.

(Source: Edward Russell - SKIFT. Read article here)