Massachusetts personal bankruptcy filings shot up last year, spiking 33 percent in 2009 from a year earlier, according to data from The Warren Group.

There were 16,033 filings under Chapter 7 of the U.S. bankruptcy code last year, up from 12,034 in 2008.

A Chapter 7 bankruptcy allows filers to eliminate most debt after non-exempt assets are used to pay off creditors. It is the most common option for individuals who are seeking relief from their debts and accounted for 81 percent of all filings in the state in 2009.

The year brought in a flood of debtors seeking protection because of unemployment and crippled finances thanks to the loss of home equity, said Boston-based attorney Neil Burns. But the latter half of 2009 brought in people laid low by soaring credit card interest rates.

These clients had been successfully paying credit card debt, Burns said, but when interest rates rose last year, it was just enough to exhaust debtors’ finances.

"It pushed a lot of people over the edge," he said.

In 2007, 8,405 debtors filed for Chapter 7, nearly double the number in 2006.

Filings in 2005, however, soared to 22,526 filings shortly before a federal law went into effect that made it tougher and more expensive for people to file for bankruptcy protection under Chapter 7.

While Chapter 7 essentially wipes away debt, Chapter 13 requires debtors to arrange for a three- or five-year debt repayment plan.

A total of 3,511 filers sought protection under Chapter 13 in 2009, down 15 percent from 4,147 filings in 2008.

Bankruptcies under Chapter 11 rose only 6 percent, to 215 in 2009 from 202 the year before.

Peter B. McGlynn, a partner at Bernkopf Goodman in Boston, said he expects commercial bankruptcies to escalate this year as commercial real estate foreclosures increase.