Nearly three decades later, the credit card—along with a raft of other perks—accounted for $8 billion, or about 10%, of Delta’s revenue in 2025. According to Delta CEO Ed Bastian, the co-branded credit card’s spending nears 1% of the U.S. GDP annually—a figure that reflects the sheer volume of transactions flowing through the partnership across millions of cardholders.
But the relationship wasn’t always so seamless.
For years, Delta and Amex struggled with a fundamental question: whose customer was it?
“We would have difficulties with Amex because we could never figure out whose customer it was,” Bastian said. “Amex thought it was their customer because they had the credit card. Delta thought it was our customer because we’re providing the experience.”
The tension came to a head about a decade ago, when Delta sat down with Amex CEO Steve Squeri to resolve the matter. Bastian recalled what Squeri—who he now considers a close friend—told him: “It’s our customers. And let’s stop fighting about who’s getting what size slice, and figure out, how do we make the pie bigger?”
That reframe changed the trajectory of the deal.
“Those are the most successful relationships,” Bastian said. “It’s not when one brand is taking advantage of another or feeding off another. [It’s] when both brands legitimately raise up.”
The co-branded card’s importance to Delta came into sharper focus during one of the airline’s darkest chapters. After a post-9/11 slump battered the carrier, Bastian—then the CFO—pushed the company to file for bankruptcy in 2005. Delta emerged from Chapter 11 in 2007, and the following year, Amex delivered a $1 billion boost, marking the beginning of what would become one of the most lucrative partnerships in the aviation industry.
“If you ask people why they choose Delta, 80% would say because it’s Delta, because the experience the brand, the confidence I have in that company—‘That’s my airline,’” Bastian said.
“We have the largest array of any card company, and it keeps growing,” Squeri said.
Today, Delta is Amex’s largest card distributor. The Delta card accounts for 10% of Amex’s worldwide billings, and Delta cardholders represent 30% of Amex’s U.S. consumer spend, according to Bastian.
And the growth isn’t slowing.
“Even though we’re the largest distribution outlet, we’re growing faster than any of the other distribution outlets they have at a double-digit clip still today,” Bastian said. “That’s making the pie bigger.”
