Capital One Financial said it will buy Discover Financial Services for $35 billion, in a deal that would bring together two of the nation's credit card companies as well as potentially shake up the payments industry, which is largely dominated by Visa and Mastercard.

Under the terms of the all-stock transaction, Discover Financial shareholders will receive Capital One shares valued at nearly $140. That's a significant premium to the $110.49 that Discover shares closed at Friday.

The deal marries two of the largest credit card companies that aren't banks first, like JPMorgan Chase and Citigroup, with the notable exception of American Express. It also brings together two companies whose customers are largely similar: often Americans who are looking for cash back or modest travel rewards, compared to the premium credit cards dominated by AmEx, Citi and Chase.

“This marketplace that’s dominated by the big players is going to shrink a little bit more now,” said Matt Schulz, chief credit card analyst at LendingTree.

It also will give Discover's payment network a major credit card partner in a way that could make the payment network a major competitor once again. The U.S. credit card industry is dominated by the Visa-Mastercard duopoly with AmEx being a distance third place and Discover an even more distant fourth place.

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With its purchase of Discover, Capital One is betting that Americans’ will continue to increasingly use their credit cards and keep balances on those accounts to collect interest. In the fourth quarter of 2023, Americans held $1.13 trillion on their credit cards, and aggregate household debt balances increased by $212 billion, up 1.2%, according to the latest data from the New York Federal Reserve.

As they run up their card balances, consumers are also paying higher interest rates. The average interest rate on a bank credit card is roughly 21.5%, the highest it’s been since the Federal Reserve started tracking the data in 1994.

At the same time, the two lenders have had to boost their reserves against the possibility of rising borrower defaults. After battling inflation for more than two years, many lower- and middle-income Americans have run through their savings and are increasingly running up their credit card balances and taking on personal loans.

The additional reserves have weighed on both banks’ profits. Last year, Capital One’s net income available to common shareholders slumped 35% versus 2022, as its provisions for loan losses soared 78% to $10.4 billion. Discover’s full-year profit sank 33.6% versus its 2022 results as its provisions for credit losses more than doubled to $6.02 billion.

Discover’s customers are carrying $102 billion in balances on their credit cards, up 13% from a year earlier. Meanwhile, the charge-off rates and 30-day delinquency rates have climbed.

Beyond boosting bank deposits and loan accounts, the acquisition would give Capital One access to the Discover payment processing network. While smaller than industry giants Visa and Mastercard, the Discover network will enable Capital One to get revenue from fees charged for every merchant transaction that runs on the network.

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Discover has been operating under heightened scrutiny from regulators. Last summer, the company disclosed that beginning around mid-2007, it incorrectly classified certain card accounts into its highest merchant pricing tiers. The company also received an unrelated consent order from the Federal Deposit Insurance Corporation over its customer compliance management.

Analysts at Citigroup say the regulatory issues may have prompted the sale.

“We are surprised that DFS would sell, but suppose that its regulatory challenges such as its recent October FDIC consent order and the card product misclassification issue may have opened the door for the board to consider strategic alternatives that it may not have in the past,” wrote analysts Arren Cyganovich and Kaili Wang in a note to clients.

It's unclear whether the deal will pass regulatory scrutiny. Nearly every bank issues a credit card to customers but few companies are credit card companies first, and banks second. Both Discover — which was long ago the Sears Card — and Capital One started off as credit card companies that expanded into other financial offerings like checking and savings accounts.

Consumer groups are expected to put heavy pressure on the Biden Administration to make sure the deal is good for consumers as well as shareholders.

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“The proposed transaction is rather out of sync with the times. But big banks don’t worry too much about consumers and they are always out to reduce competition," said Carter Dougherty with Americans for Financial Reform.