When choosing a beneficiary for a retirement plan, it is important to understand how your spouse will be treated under the plan. Surviving spouses are treated differently under 401(k)s and individual retirement accounts (IRAs). While a 401(k) provides protections for a surviving spouse, an IRA does not.
Because the 401(k) is an employee-based retirement system, it is governed by a federal law, the Employee Retirement Income Security Act of 1974 (ERISA). Under ERISA, a surviving spouse is usually the automatic beneficiary of a retirement plan (There may be some exceptions. For example, the spouse may have to be married to the employee for a certain amount of time). The spouse must consent in writing if the employee wishes to name someone else as the beneficiary.
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