Retirement & Savings

What Is a Solo 401(k)?

A solo 401(k), or individual 401(k), is a US retirement plan for self-employed people and business owners with no employees other than a spouse. The owner can contribute both as the employee (elective deferrals) and as the employer (profit-sharing contributions), up to combined annual limits.

Two Kinds of Contributions

Employee deferrals can be made up to the annual 401(k) limit; employer contributions are based on a percentage of compensation.

Roth Option

Many solo 401(k) plans allow Roth deferrals.

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🔗 Related Terms

SEP IRA 401(k) Plan Roth 401(k) Self-Employment Tax

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Last updated: September 29, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.