A little over a year into its planned Discover integration, Capital One has completed the conversion of roughly 25 million debit cards into the Discover Network. The company is now turning its attention to credit card accounts.
During its quarterly earnings call, Capital One said it had begun testing select credit cards on Discover’s payment rails, moving away from the Visa network where those accounts had previously operated. The flagship Venture X card has remained on Visa, along with co-branded cards for T-Mobile, Kohl’s, and Bass Pro Shops/Cabela’s, though that could change as the migration progresses.
“We are leaning hard into right now testing originating legacy Capital One branded accounts on the Discover network as well as testing the conversion of existing Capital One accounts to the Discover network,” Chairman and CEO Richard Fairbank said during the call.
A Massive Migration
Capital One plans to begin converting Discover’s existing card portfolio, known as the back book, later in July, with additional migration waves scheduled for October and January. The company said it remains on track to achieve the full $2.5 billion in expected merger-related synergies by the second half of 2027.
The Capital One-Discover merger, which closed in May 2025, has been rolling out in stages. One challenge is Discover’s more limited international acceptance compared with Visa and Mastercard. During the earnings call, Capital One said it is working to expand Discover acceptance globally, with a focus on markets including Mexico, the Caribbean, Canada, and the United Kingdom.
“While some wonder why this is taking so long, the conversion appears to be moving at an appropriate pace,” said Brian Riley, Director of Credit at Javelin Strategy & Research. “Capital One is undertaking the largest card integration in the payments industry. It is complicated by the assimilation of the Discover network, more than 71 million cards, plus the debit function and the Pulse Network. And the Diners Card, which is a global ecosystem unto itself.”
A Slower Start for Discover
Discover’s performance has been mixed since becoming part of Capital One. Legacy Discover purchase volume grew just under 2% year over year, while Discover card loans declined 1.5%. By comparison, purchase volume across other Capital One businesses, including recently acquired commercial payments and expense management fintech Brex, increased about 14%.
Capital One executives said the slowdown in Discover card loan growth was expected and likely temporary. Discover had already pulled back on new account origination before the acquisition, which weighed on near-term growth.
