Discover's provision for credit losses fell 17% to $1.24 billion in the quarter ended March 31 from about $1.50 billion in the year-ago period. The company reported net interest income of $3.56 billion for the first quarter, up over 2% from the same quarter last year. Net interest margin, a key gauge of profitability, expanded 115 basis points to 12.18% helped by Discover's sale of its student loan portfolio to Carlyle and KKR in July 2024, the company said. Capital One Financial (NYSE: COF ), whose $35.3 billion all-stock deal to acquire Discover was approved by U.S. banking regulators last week, also recorded a jump in first-quarter profit on Tuesday, helped by higher interest income. The deal, which is set to close on May 18, will create the biggest U.S. credit card issuer by balance.