The U.S. banking industry lost more than $26 billion in the last three months of 2008, the first quarterly loss in 18 years.
The number of banks that regulators classify as "troubled" rose nearly 50 percent during the same quarter.
Banks lost money as the recession made it harder for borrowers to repay loans. Banks were also hurt by losses on their investments in stocks and other areas.
The U.S. government's Federal Deposit Insurance Corporation says the number of banks that actually fail is growing, with 25 going under last year.
Although the weak economy has resulted in increased losses for banks, the American Bankers Association said Thursday 97 percent of all the country's banks are still rated "well capitalized" - meaning they have a significant financial buffer against losses.
There are more than 8,000 banks in the United States insured by the FDIC.