Various data suggest that advice is eschewed by many workers. According to the IRS, Americans shelled out roughly $5.7 billion in early-withdrawal penalties in 2011, slightly down from $5.8 billion in 2010. This means that in those two years alone, workers shaved their retirement savings by more than $100 billion before they were supposed to.
Moreover, 21 percent of 401(k) participants had loans outstanding against their accounts at year-end 2011, according to the Employee Benefit Research Institute. Those outstanding loans, which involve no penalty or tax event but do come with certain stipulations, averaged 14 percent of the remaining account balances.
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As illustrated by those sheer numbers alone, sometimes life can get in the way of even the best retirement-planning intentions.
"Sometimes your 401(k) is the only place you can go for [money]," said Mary Ballin, a senior certified financial planner with Mosaic Financial Partners. "Say a spouse lost his job but you have house payments, children's education costs and things like that. You have to pay those bills."