Ohio Revised Code Title LVII. Taxation § 5703.58

(A) Subject to divisions (B) and (D) of this section, the tax commissioner shall not make or issue an assessment for any tax payable to the state that is administered by the tax commissioner, or any penalty, interest, or additional charge on such tax, after the expiration of ten years, including any extension, from the date the tax return or report was due when such amount was not reported and paid, provided that the ten-year period shall be extended by the period of any lawful stay to such assessment. As used in this section, “assessment” has the same meaning as in section 5703.50 of the Revised Code.

(B) Subject to division (D) of this section, the tax commissioner shall not make or issue an assessment against any person for any tax due under Chapter 5741. of the Revised Code, or any penalty, interest, or additional charge on such tax, after the expiration of seven years, including any extension, from the date the tax return or report was due if the amount of tax due was not reported and paid, provided that the seven-year period shall be extended by the period of any lawful stay to the assessment. The commissioner shall not make or issue an assessment against a consumer for any tax due under Chapter 5741. of the Revised Code, or for any penalty, interest, or additional charge on such tax, if the tax was due before January 1, 2008.

(C) This section does not apply to either of the following:

(D) This section does not authorize the assessment or collection of a tax for which the applicable period of limitation prescribed by law has expired and for which no valid assessment has been made and served as prescribed by law.