Despite an aging workforce, many small employers don't offer retirement plans, according to a new study by SurePayroll, a Glenview, Ill.-based payroll firm.

Of 236 small-business owners recently polled, only about a third said they offer 401 (k) plans, while about half didn't offer any retirement plans at all. Many said the current state of the economy was making difficult for employers to provide benefits.

"Saving for retirement is no longer an option -- it's crucial for the stability of our future economy," Michael Alter, the firm's president, said in a statement.

He added that 401(k) plans can help employees feel more secure during a recession and offer a competitive edge to businesses competing for top talent.

While most owners don't provide retirement plans in benefits packages for workers, a majority have plans for their own retirement savings, an earlier SurePayroll survey found. Most were confident about achieving their retirement goals.