401(a)

In the United States, a 401(a) plan is a tax-deferred retirement savings plan set up by an employer. The 401(a) plan allows for contributions by the employee, the employer, or both. Contribution amounts, whether dollar-based or percentage-based, eligibility, and vesting schedule are all determined by the sponsoring employer.

The term comes from subsection 401(a) of the Internal Revenue Code (Title 26 of the United States Code).

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