The worsening situation came despite continuing efforts by lenders to help borrowers manage their payments by modifying loan terms, working out long-term repayment plans and other actions.

"You have more people going into default and a higher percentage of the properties going back to the banks," said Rick Sharga, RealtyTrac's vice president of marketing.

The U.S. foreclosure rate last month was one filing for every 534 homes.

Nevada led the nation, with 6,087 properties receiving at least one filing, up 95 percent from a year earlier but down 45 percent from December, the firm said. That translates to a rate of about one foreclosure for every 167 households.

The Cape Coral-Fort Myers area in Florida posted the highest foreclosure rate of any metro area in the nation, with one of every 86 homes in some stage of foreclosure, said RealtyTrac.

Stockton, Calif., was ranked second, with one of every 97 homes involved in a foreclosure filing, while the Riverside-San Bernardino metro area in Southern California had the third-highest foreclosure rate with filings for one of every 101 properties.

January's tally represented an 8 percent increase from December.

RealtyTrac follows default notices, auction sale notices and bank repossessions. Lenders typically consider borrowers delinquent after they fall three months behind on mortgage payments.

Attempts to help struggling home owners have fallen short.

"The loan workout modification programs aren't having a significant material effect on keeping properties from going back to the banks," Sharga said.

One dramatic trend last month was a 90 percent spike in the number of properties that were repossessed by banks, compared with January 2007.

"It suggests that there's little or no equity in a lot of these homes, because they're not even being sold to investors at auctions, and it suggests a continuing weakness in a lot of markets in terms of real estate sales," Sharga said.

Falling home values and tighter lending standards have extended the housing slump, making it tougher for homeowners to sell their homes or refinance when they face mortgage payments they can't afford.

During the past year, 30 states saw an increase in the number of homes that had received at least one filing.

Rounding out the top 10 states with the highest foreclosure rates after Nevada were California, Florida, Arizona, Colorado, Massachusetts, Georgia, Connecticut, Ohio and Michigan.

California had 57,158 properties reporting at least one filing, the most of any state.