Since all monies contributed to a 401(k) plan are protected by federal laws, whether at a current or previous employer, the money is still safeguarded. The best method for locating money in a 401(k) with a previous employer is to contact the employer directly, notes 401khelpcenter.com.
An additional way to locate your 401(k) money is to contact the administrative firm of the plan, which is shown on plan statements and annual Form 5500. You can also check to see if you are listed as a missing participant on The National Registry, recommends 401khelpcenter.com. Another resource is the Abandoned Plan Database with the U.S. Department of Labor.