US commercial bankruptcy filings jumped 56% in April from a year earlier, court records show
Business bankruptcy filings rose to 5,173, while total bankruptcy filings, including those by individuals, were up by 37% to 93,096.
The figures were compiled from US court records by data provider AACER.
Tropicana Entertainment, which owns casinos in Atlantic City and Las Vegas, has become the latest firm to file for bankruptcy protection.
Known as Chapter 11, it allows a company time to reorganise and devise a plan to keep its businesses alive and pay creditors over time.
"This is the first step in making things better," Tropicana's president, Scott C Butera, told the Associated Press news agency.
Bankruptcies have risen as the US economy has been hit by a slowdown in the housing market and turmoil in financial markets.