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For you and your family
Standard mileage and other information

Forms and Instructions

Individual Tax Return
Instructions for Form 1040
Request for Taxpayer Identification Number (TIN) and Certification
Request for Transcript of Tax Return


Employee's Withholding Allowance Certificate
Employer's Quarterly Federal Tax Return
Employers engaged in a trade or business who pay compensation
Installment Agreement Request

Popular For Tax Pros

Amend/Fix Return
Apply for Power of Attorney
Apply for an ITIN
Rules Governing Practice before IRS

Retirement Topics - Who Can Participate in a Qualified Plan?

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.

Additional resources

Publication 560, Retirement Plans for Small Business (SEP, SIMPLE, and Qualified Plans)
Publication 4222, 401(k) Plans for Small Businesses
Publication 4531, 401(k) Plan Checklist