A Solo401k is designed to be used by you and your spouse.

In the Solo 401K, you are re the employee and you are also the employer. There are no matching contributions because the plan is designed to be as flexible and as capable as any retirement plan can possibly be allowed by law in the U.S. This might mean that some years you will make employer contributions and in other years you won’t. This is to allow the greatest flexibility within the plan.
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