Mo. Rev. Stat. § 143.621
Current with changes from the 2023 Legislative Session
Sixty days after the date on which it was mailed (one hundred fifty days if the taxpayer is outside the United States), a notice of deficiency shall constitute a final assessment of the amount of tax specified together with interest, additions to tax, and penalties except only for such amounts as to which the taxpayer has filed a protest with the director of revenue.
§ 143.621, RSMo
Effective 1/1/1984