Using an employer-sponsored 401(k) plan can be a great way to save for retirement. The downside of 401(k)s, though, is that they're tied to a specific employer. As a result, when you switch jobs, your 401(k) money won't automatically switch with you. Rather, in many cases, it will stay in your account. Let's run through various ways to locate 401(k) money from previous employers.

Contact your old employer
The most obvious way to find previous 401(k) accounts is to contact your old employer directly. The employer's human resources department should have records of your current retirement-plan account and what assets are inside it. Your former employer will also be able either to get you the forms necessary to roll over your retirement money to a different 401(k) or to an IRA (we have much more information on IRAs at our IRA Center), or to give you contact information for any outside financial institution overseeing the plan on your employer's behalf. By following the appropriate instructions you get, you'll be able to move your retirement money where you want.

Refer to an old statement
If you don't have contact information for your old employer, another possibility is to look through your records to find an old 401(k) statement. Statements will typically have the information you need to get in contact with either your employer or a plan administrator. Then, you can inquire about your options for moving money and get the information you need to do so.

Search for unclaimed retirement benefits
Employers often have trouble contacting former employees to claim their retirement benefits. To facilitate matching up employers and employees, a private company that handles processing of retirement distributions nationwide set up the National Registry of Unclaimed Retirement Benefits. This service will allow you to perform a free search for any retirement plan balances in your name.

In order to appear in the database, your employer must participate in the service. However, the service provides some benefits for employers to help it meet its legal requirements. That increases the likelihood that you might find lost 401(k) balances there.

Look for corporate mergers
Sometimes, your former employer might no longer be an independent business because another company has purchased it. In that case, your old 401(k) plan might have been merged into the acquiring company's own 401(k) plan. By looking for news related to your former employer, you might track down the surviving company's name and find contact information.

Most of the time, employers are good about getting 401(k) plan information to you immediately after your quit your job. In some cases, though, looking for previous 401(k) accounts will give you an unexpected windfall.

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