Do all solo 401k plans allow voluntary after-tax contributions by default?
ANSWER:
Not all solo 401k plan allow for voluntary after-tax contributions. The solo 401k plan document provider ultimately decides whether to allow for voluntary after-tax contributions as well as Roth contributions to the plan. Solo 401k Plan providers like Fidelity Investments, Charles Schwab and Vanguard do not allow for voluntary after-tax contributions to solo 401k plans while self-directed solo 401k providers such as My Solo 401k Financial does allow for both roth and voluntary after-tax solo 401k contributions as well as in-plan conversions and conversions to Roth IRAs.