It turns out that many Americans are missing out on parts of their retirement savings. With frequent job changes, and confusing enrollment practices, Americans are leaving 401(k) plans and other retirement vehicles that they might not even know exist behind them . Anne Tergesen writes at The Wall Street Journal:

As Americans jump from job to job, they are leaving more 401(k)-style accounts and pension benefits with ex-employers. Some lose track of the money, forfeiting a piece of their retirement security.

While no one keeps exact tabs on the number of lost retirement accounts, human-resources consulting firm Aon Hewitt estimates that as many as 30% of all pension accounts may ultimately fall into this category—either because a plan can no longer locate former employees who move or change names, or because a participant forgets that he or she is entitled to benefits or cannot find a past employer that changed its name.

When the U.S. Department of Labor recently studied the public filings of 50 large pension plans in the six states that fall within its Philadelphia office’s jurisdiction, it found more than 70,000 participants older than 65—the age at which pension plans typically start paying benefits—who were entitled to “well over $100 million in annual benefits” but weren’t collecting them, says Michael Schloss, director of the Philadelphia Regional office.

Read more from the WSJ here.

If you have lost a pension account, you don’t have to be Sherlock Holmes to find it, there is help available to you. The Pension Benefit Guaranty Corp, and the Dept. of Health and Human Services Administration for Community Living are both available to help employees with lost pensions. You can also visit, or to find recently filed pension annual reports known as Form 5500s.

Once you find your 401(k)s, here’s what you should know about rolling them over.