In general, employees must be in their employer's qualified plan (for example, profit-sharing, 401(k) or defined benefit plan) if they are: At least age 21 and Have at least 1 year of service a plan other than a 401(k) plan can require an employee to accrue 2 years of service, but if it does, then the employee is immediately vested in their accrued benefit) The employer must follow the eligibility rules in the plan document, which can be less restrictive than those listed above. Example: Employer B's plan allows employees to participate in its profit-sharing plan at age 18. Employees should review the Summary Plan Description that their employer gives to them to determine the eligibility requirements for their plan. An employee is eligible to participate in his or her employer's retirement plan when he or she meets certain conditions stated in the plan. The law permits each type of plan to have different requirements for participation in the plan. SEP or SARSEP plan SIMPLE IRA plan Qualified plan (for example, 401(k), profit-sharing, defined benefit) 403(b) plan 457(b) plan Additional resources Publication 560, Retirement Plans for Small Business (SEP, SIMPLE, and Qualified Plans) Publication 4222, 401(k) Plans for Small Businesses PDF Publication 4531, 401(k) Plan Checklist PDF
