Filing returns; extensions; payment of tax.
(1) Filing returns. Every corporation, except a corporation all of whose income is exempt from taxation and except as provided in sub. (1m), shall furnish to the department a true and accurate statement, on or before the date on which the corporation is required to file for federal income tax purposes, not including any extension, under the Internal Revenue Code, in the manner and form and setting forth the facts the department deems necessary to enforce this chapter. Every corporation that is required to furnish a statement under this subsection and that has income that is not taxable under this subchapter shall include with the corporation’s statement a report that identifies each item of the corporation’s nontaxable income. The statement shall be subscribed by the president, vice president, treasurer, assistant treasurer, chief accounting officer, or any other officer duly authorized so to act. In the case of a return made for a corporation by a fiduciary, the fiduciary shall subscribe the return. The fact that an individual’s name is subscribed on the return shall be prima facie evidence that the individual is authorized to subscribe the return on behalf of the corporation.
(1m) Unrelated business income statement. Every corporation subject to a tax on unrelated business income under s. 71.26 (1) (a), if that corporation is required to file for federal income tax purposes, shall furnish to the department a true and accurate statement on or before the date on which the corporation is required to file for federal income tax purposes, not including any extension, under the Internal Revenue Code. The requirements about manner, form, and subscription under sub. (1) apply to statements under this subsection.
(2) Copies of federal return. Each corporation that is required to file a return under this section shall file with that return a copy of its federal income tax return for the same taxable year.
(3) Inactive corporations. Whenever a corporation has been completely inactive for an entire taxable year, in lieu of filing the statements and information otherwise required by this section, it may file a declaration, on a form to be provided by the department, subscribed by its president, if a resident of this state, and, if not a resident, then by another officer residing in this state, attesting to such inactivity. Such declaration must be filed prior to the otherwise due date for its Wisconsin return for such taxable year. Thereafter the corporation need not file such statements or information for any subsequent year unless specifically requested to do so by the department or unless in a subsequent year the corporation has been activated or reactivated.
(4) Filing returns by receiver, trustee in bankruptcy or assignee. If a receiver, trustee in bankruptcy or assignee, by order of a court, by operation of law or otherwise, has possession of all or substantially all of the property or business of a corporation, whether or not such property or business is being operated, such receiver, trustee or assignee shall make the return of income for such corporation in the manner and form that corporations are required to make such returns.
(5) Department may require filing. Nothing contained in this section shall preclude the department from requiring any corporation to file a return when in the judgment of the department a return should be filed.
(6) Changing reporting period.