Klarna (NYSE: KLAR) and Southwest Airlines announced a long-term partnership to offer flexible payment options to Southwest customers across the United States, according to a press release from Klarna.

Starting later this year, travelers booking on Southwest.com and the Southwest app will be able to choose from several payment options at checkout, including paying in full, splitting the cost into four interest-free installments, or financing their trip over time.

Southwest served over 134 million customers in 2025 and carries more nonstop domestic passengers than any other U.S. airline, according to the U.S. Department of Transportation's quarterly Airline Origin & Destination Survey through Q4 2025.

"Southwest has spent over 50 years making flying accessible to more Americans, and we're proud to be the partner that takes that mission one step further," said David Sykes, Chief Commercial Officer at Klarna.

"Southwest is focused on giving more choice to Customers when they travel with us," said Corbitt Burns, Managing Director Loyalty & CoBrand at Southwest Airlines. "With Klarna's flexible payment options, customers gain another convenient way to book flights."

Klarna reports 119 million active users across 26 countries and processes approximately 3.4 million transactions per day.