A 401(a) plan refers to an IRC Section 401(a) employer-sponsored money-purchase plan to save for retirement, notes both Zack's Finance and the Internal Revenue Service website. There are not multiple types of 401(a) plans, as the plan refers to a specific section of the Internal Revenue Code.
A 401(a) retirement plan offers tax advantages for employees, explains Zack's Finance. An employer determines how much a company contributes to a plan and the requirements that an employee must meet to receive the contributions. The employer also determines whether the contributions are made on a before-tax or after-tax basis. All contributions are subject to certain limitations that vary each tax year.