Extension of time to file.

Returns of natural persons and fiduciaries that require a statement of amounts or information contained or entered on a corresponding return under the internal revenue code shall be filed within the time fixed under that code for filing of the corresponding federal return. Any extension of time granted by law or by the internal revenue service for the filing of that corresponding federal return extends the time for filing under this chapter if a copy of the taxpayer’s application to the internal revenue service requesting the extension is filed with the return under this chapter or if a copy of any request for an extension required by the internal revenue service is filed with the return under this chapter or at an earlier date that the department prescribes by rule and if the taxpayer pays the Wisconsin tax in the manner applicable to federal income taxes under the internal revenue code. Taxes payable upon the filing of the return do not become delinquent during the period of an extension but are subject to interest at the rate of 12 percent per year during such period except as follows: