The Roth 401(k). A Roth 401(k) account works much like a Roth IRA, but there is no income limit to participate, and you are required to take the minimum distributions that would be required from a Traditional IRA beginning at age 70½.There is also a Roth version of the 403(b) plan. Roth 401(k) account works much like a Roth IRA, but there is no income limit to participate, and you are required to take the minimum distributions that would be required from a Traditional IRA beginning at age 70½.