Sept. 15 (Bloomberg) -- JPMorgan Chase & Co., Bank of America Corp. and Citigroup Inc., the biggest U.S. credit- card lenders, said defaults climbed in August as the unemployment rate jumped and the impact of tax refunds waned.

American Express Co. was the only one of six card-issuers releasing data today to report an improvement in the rate of both defaults and delinquencies, a signal of future write-offs.

The industry’s data may signal that the second quarter’s improvement will be short-lived as tax refunds and federal efforts to stimulate the economy run out. Defaults tend to track the jobless rate, which dipped in July for the first time since the start of the recession before resuming its climb to 9.7 percent in August.

The rise “suggests that the past several months’ data may have benefited from seasonal factors and that the consumer credit cycle has not yet run its full course,” Oppenheimer & Co. analyst Chris Kotowski wrote today in a research note.

Bank of America said write-offs rose to 14.54 percent, the highest among the six U.S. lenders reporting today. That compares with 13.81 percent in July, according to a federal filing by the Charlotte, North Carolina-based company.

Citigroup’s soured loans rose to 12.14 percent last month, from 10.03 percent, while JPMorgan said write-offs advanced to 8.73 percent from 7.92 percent in July, according to a federal filing. Both are based in New York.

Discover, Capital One

Discover Financial Services, the credit-card company that took $1.2 billion from the Treasury Department’s rescue fund, said charge-offs rose to 9.16 percent from 8.43 percent in July. The Riverwoods, Illinois-based lender is scheduled to report third-quarter results on Thursday.

Capital One Financial Corp., the third-biggest issuer of Visa Inc. credit cards, said charge-offs improved to 9.32 percent in August, from 9.83 percent.

Delinquencies, or overdue loans that haven’t been declared uncollectible yet, rose at Capital One to 5.09 percent in August from 4.83 percent. The McLean, Virginia-based bank fell 90 cents, or 2.4 percent, to $37.42 in 4:15 p.m. New York Stock Exchange composite trading. Bank of America and Citigroup both reported that delinquencies improved from July to August. Loans at least 30 days overdue fell to 7.47 percent, from 7.55 percent, at Bank of America, and to 5.38 percent, from 5.51 percent, at Citigroup.

Leading Indicator

Continued improvement in early stage delinquencies should lead to lower charge-offs later this year or in early 2010, Bank of America Chief Financial Officer Joe Price told investors today at the Barclays Global Financial Conference in New York.

Bank of America fell 1.2 percent to $16.79 and Citigroup dropped 8.9 percent to $4.12.

American Express shares added 2.2 percent to $34.65 after the company said delinquencies fell to 4.1 percent in August, from 4.2 percent. Write-offs also dropped to 9 percent, from 9.2 percent, the fourth straight monthly improvement. Chief Executive Officer Kenneth Chenault told investors on Aug. 5 that the decline in write-offs may represent real improvement beyond seasonal influences.

Charge-offs on an owned basis, meaning only those kept on the company’s balance sheet, rose to 10.2 percent from 9.9 percent.

Moody’s Investors Service has said it expects average U.S. charge-offs to peak at 12 percent to 13 percent in 2010.

To contact the reporter on this story: Peter Eichenbaum in New York at peichenbaum@bloomberg.net

Last Updated: September 15, 2009 17:52 EDT