Americans have left tens of millions of 401(k) accounts behind at former employers. The money is still yours, and it is still invested somewhere. Finding it is mostly a matter of finding the plan, and the plan is a matter of public record. Here is the order that works. (Short on time? The lookup tool does step one for you.)
1. Look up your former employer's plan here
Every large employer plan files an annual report with the Department of Labor, and this site indexes them all. Search for your former employer, open its plan page, and follow the "Verify on EFAST2" link at the bottom to the plan's official filing. The filing lists the plan administrator and their contact information, which is who actually holds the records for your account. Call or write them with your name, Social Security number, and approximate dates of employment.
2. Ask your former employer directly
If the company still exists, HR or payroll can tell you who the plan's recordkeeper is (Fidelity, Empower, Vanguard, Principal, and similar firms hold most accounts). If the company was acquired, the acquirer's HR usually inherited the plan records; the plan page here will show whether the plan itself was merged or terminated in its filing history.
3. The government's Lost and Found database
The Department of Labor launched a Retirement Savings Lost and Found at lostandfound.dol.gov under the SECURE 2.0 law. Know its limits before relying on it: as of early 2026 it requires identity verification through Login.gov and only serves people age 65 and older. If that is not you, the employer-lookup route above covers the same ground without the age gate.
4. Unclaimed property registries
If a plan terminated and could not find you, your balance may have been transferred out. Check the National Registry of Unclaimed Retirement Benefits (unclaimedretirementbenefits.com), your state's unclaimed property office via missingmoney.com, and, for terminated traditional pensions, the PBGC's unclaimed pension search.
5. Once you find it, decide where it should live
You can usually leave the money, roll it into your current employer's plan, or roll it into an IRA. Before deciding, compare what the old plan actually costs: its plan page here shows the reported administrative expenses against peers. A high-cost old plan is a strong argument for consolidating; an unusually cheap one may be worth keeping.
One caution: any balance under $7,000 can be force-rolled by the plan into a "safe harbor IRA" that often sits in cash with account fees. The longer a small account stays lost, the more likely it has been moved and is quietly shrinking, so the search is worth doing this week rather than someday.