Ohio Code § 5733.031

§ 5733.031.

(A) A corporation's taxable year is a period ending on the date immediately preceding

the date of commencement of the corporation's annual accounting period that includes

the first day of January of the tax year.  Except as otherwise provided, a corporation's taxable year is the same as the corporation's

taxable year for federal income tax purposes.  If a corporation's taxable year is changed for federal income tax purposes, the

taxable year for purposes of this chapter is changed accordingly but may consist of

an aggregation of more than one taxable year for federal income tax purposes.  The tax commissioner may prescribe by rule, an appropriate period as the taxable

year for a corporation that has had a change of its taxable year for federal income

tax purposes, for a corporation that has two or more short taxable years for federal

income tax purposes as the result of a change of ownership, or for a new taxpayer

that would otherwise have no taxable year. (B) A corporation's method of accounting for the base calculated under division (B) of section 5733.05 of the Revised Code shall be the same as its method of accounting for federal income tax purposes.  In the absence of any method of accounting for federal income tax purposes, income

shall be computed under such method as in the opinion of the tax commissioner clearly

reflects income. If a corporation's method of accounting is changed for federal income tax purposes,

its method of accounting for purposes of this chapter shall be changed accordingly. (C) Except as provided in division (C)(3) of this section, any of the facts, figures,

computations, or attachments required in a corporation's annual report to determine

the tax imposed by section 5733.06 of the Revised Code must be altered as the result of an adjustment to the corporation's federal income

tax return, whether the adjustment is initiated by the corporation or the internal

revenue service, and such alteration affects the corporation's liability for the tax

imposed by section 5733.06 of the Revised Code , the corporation shall file an amended report with the tax commissioner in such form

as the commissioner requires.  The amended report shall be filed not later than one year after the adjustment has

been agreed to or finally determined for federal income tax purposes or any federal

income tax deficiency or refund, or the abatement or credit resulting therefrom, has

been assessed or paid, whichever occurs first. (1) In the case of an underpayment, the amended report shall be accompanied by payment

of an additional tax and interest due and is a report subject to assessment under section 5733.11 of the Revised Code for the purpose of assessing any additional tax due under this division, together

with any applicable penalty and interest.  It shall not reopen those facts, figures, computations, or attachments from a previously

filed report no longer subject to assessment that are not affected, either directly

or indirectly, by the adjustment to the corporation's federal income tax return. (2) In the case of an overpayment, an application for refund may be filed under this

division within the one-year period prescribed for filing the amended report even

if it is filed beyond the period prescribed in division (B) of section 5733.12 of the Revised Code if it otherwise conforms to the requirements of such section.  An application filed under this division shall claim refund of overpayments resulting

from alterations to only those facts, figures, computations, or attachments required

in the corporation's annual report that are affected, either directly or indirectly,

by the adjustment to the corporation's federal income tax return unless it is also

filed within the time prescribed in division (B) of section 5733.12 of the Revised Code .  It shall not reopen those facts, figures, computations, or attachments that are

not affected, either directly or indirectly, by the adjustment to the corporation's

federal income tax return. (3) A taxpayer is not required to file an amended report, and is not permitted to file

an application for refund, under this section on or after January 1, 2024.