Nobody wants to miss out on money that’s rightfully theirs, yet many people do without even realizing it.

That includes retirement savings. According to Capitalize and the Center For Retirement Research, an estimated 31.9 million 401(k) accounts holding roughly $2.1 trillion have been forgotten or left behind by their owners (1).

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Losing track of retirement funds is easier than it sounds. Job changes, a skipped roll over, a company merger or name change or simply losing touch with a former employer can be enough for an old account to slip off the radar. And we’re not talking about just a few dollars: Some people unknowingly leave behind $20,000 or more in a former workplace plan (2).

The money doesn’t disappear, but it also won’t automatically be paid out. In most cases, account holders must actively track it down and claim it.

The good news is that new federal tools, together with longstanding state programs, are making it easier than ever to locate forgotten money and potentially recover significant sums you didn’t even know existed.

To help workers reconnect with retirement savings they may have lost track of, the U.S. Department of Labor (DOL) launched the Retirement Savings Lost and Found database.

This free tool lets users search for retirement plans linked to their name through a secure identity verification process. While it does not show account balances, it provides contact information for plan administrators, giving people a starting point to track down money that may still be sitting in an old 401(k) or pension (3).

In its first year, 236,269 users tried the database, and about 29.5% of them were able to locate at least one old workplace retirement plan, according to the DOL. One important limitation is that the database only includes information for workers age 65 and older. The DOL said coverage may expand over time, but, for now, the tool doesn’t cater to younger people (2).

Other ways to track down forgotten retirement savings include:

Contact former employers directly, especially if you worked there for several years or contributed regularly to a 401(k).

Check old paperwork or emails for plan administrator names, account numbers or rollover notices.

Search the National Registry of Unclaimed Retirement Benefits, which can help locate pensions and other retirement plans tied to former employers (4).

Look for default IRAs, also called automatic rollover or safe harbor IRAs, which employers may have opened automatically if your balance was small when you left a job. They also get created if you do not respond to notices from the former employer. These may be found in the database FreeERISA (5).

Tracking down retirement funds can be tedious and time-consuming, but those efforts may eventually pay off. The Pension Action Center at the University of Massachusetts Boston reports that clients using these tools have uncovered everything from $350-per-month annuity payments to forgotten 401(k) accounts worth tens of thousands (2).

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It’s not just retirement accounts that go missing. According to the National Association of Unclaimed Property Administrators (NAUPA), more than 30 million people across the country have other unclaimed property waiting for them, ranging from small refunds to substantial sums.

Unclaimed property can come from a variety of sources, including:

Dormant bank or credit union accounts

Uncashed paychecks or refunds

Utility deposits

Insurance payouts or dividends

Stocks, bonds or mutual funds

Inheritances from deceased relatives whose heirs couldn’t be located

Often, these assets go unclaimed because people move without updating their address, change their name or never realize they are entitled to it (6).

In most cases, unclaimed property isn’t returned automatically. Companies must turn it over to the state under escheatment laws, and it stays in state custody until the owner — or their heir — claims it (7).

Some states are experimenting with ways to return assets to their rightful owners. Pennsylvania’s Money Match program, for example, automatically returns unclaimed property valued up to $500 to eligible owners, mailing checks directly to residents (8). Meanwhile, in South Carolina, one lucky resident received more than $763,000 in unclaimed cash and stocks belonging to a parent who had died many years earlier (9).

These examples are exceptions. Usually, it’s up to individuals to search for unclaimed property. Here’s how to get started:

Search MissingMoney.com, the national database supported by NAUPA, which links to participating state programs.

Check individual state unclaimed-property websites for every state where you’ve lived, worked or owned property.

Search the names of deceased relatives: inheritances and insurance proceeds are a common source of unclaimed funds. Check for retirement accounts and other accounts, using state and local resources.

Check again periodically, since new property is added to state databases every year.

Searches are usually free, and you never know what you might find.

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We rely only on vetted sources and credible third-party reporting. For details, see our editorial ethics and guidelines.

Capitalize (1); CNBC (2); U.S. Department of Labor (3); National Registry of Unclaimed Retirement Benefits (4); Marathon Financial Group (5); CNN (6); National Association of Unclaimed Property Administrators (7); Pennsylvania Treasury (8); State Treasurer of South Carolina (9)

This article provides information only and should not be construed as advice. It is provided without warranty of any kind.