In this week's @TheEconomist, I wrote about the special relationship between US airlines, their loyalty programs, and their credit card partners. US airlines tend to be profitable, but they lose money on their passenger operations.

Airlines instead make it up with vast sales of frequent flyer miles to banks, who then reward credit card spenders with such miles. The transfers are significant: American Express pays around $8bn a year to Delta airlines (Delta's entire operating profit for 2024 was $6bn)

No major US airline would have been profitable last year without revenue associated with loyalty programs. And only United would have been profitable without credit card co-brand revenue.