Statutes of limitations, assessments and refunds; when permitted
Wis. Stat. § 71.77
in effect(1) Additional assessments and corrections of assessments by office audit or field investigation may be made of income of any taxpayer if notice under s. 71.74 (11) is given within the time specified in this section.
(2) With respect to assessments of a tax or an assessment to recover all or part of any tax credit under this chapter in any calendar year or corresponding fiscal year, notice shall be given within 4 years of the date the income tax or franchise tax return was filed.
(2m) Notwithstanding sub. (2), the department of revenue may assess a deficiency related to a contribution to the capital of the taxpayer, as defined in section 118 (c) of the Internal Revenue Code, within 4 years after the department receives notice by the taxpayer, in the manner that the department prescribes, of any of the following:
(a) The amount of the expenditure under section 118 (c) (2) (A) of the Internal Revenue Code.
(b) The intent of the person against whom the deficiency is to be assessed not to make the expenditure under section 118 (c) (2) (A) of the Internal Revenue Code.
(c) Expiration of the time period under section 118 (c) (2) (B) of the Internal Revenue Code and failure of the person against whom the deficiency is to be assessed to make the expenditure under section 118 (c) (2) (B) of the Internal Revenue Code.
(2n) Notwithstanding sub. (2), the department may make an assessment within one year of receiving notice of revocation from the Wisconsin Economic Development Corporation to recover all or a part of any tax credit claimed by a taxpayer, but revoked by the corporation.
(3) Irrespective of sub. (2), if any person has filed an incorrect income tax or franchise tax return for any year with intent to defeat or evade the income tax or franchise tax assessment provided by law, or has failed to file any income tax or franchise tax return for any of such years, income of any such year may be assessed when discovered.
(4) Irrespective of sub. (3), if additional assessments are made for any period more than 6 years before the year in which the assessment is made, the burden of proof shall rest with the state to prove its case by a preponderance of the evidence.
(5) The limitation periods provided in this section may be extended by written agreement between the taxpayer and the department prior to the expiration of such limitation periods or any extension of such limitation periods. During any such extension period, the department may issue an assessment or a refund, and the taxpayer may file a claim for a refund, relating to the year which the extension covers. Subsection (4) shall not apply to any assessment made in any such extended period.
(6) Section 990.06 shall have no application to the provisions of this section.
(7) Notwithstanding any other limitations expressed in this chapter, an assessment or refund may be made:
(a) If notice of assessment is given within 6 years after a return was filed and if on that return the taxpayer reported for taxation, or the taxpayers jointly reported for taxation, less than 75 percent of the net income properly assessable, except that no assessment of additional income may be made under this subsection for any year beyond the period specified in sub. (2) unless the aggregate of the taxes on the additional income of such year is in excess of $100 in the case of a return other than a joint return or $200 in the case of a joint return.
(b) If notice of assessment or refund is given to the taxpayer within 180 days of the date on which the department receives a report from the taxpayer under s. 71.76 or within such other period specified in a written agreement entered into prior to the expiration of such 180 days by the taxpayer and the department. If the taxpayer does not report to the department as required under s. 71.76, the department may make an assessment against the taxpayer or refund to the taxpayer within 4 years after discovery by the department.
(c) When an election is made under s. 71.745 (9), with respect to assessments of a tax or an assessment to recover all or part of any tax credit under this chapter in any calendar year or corresponding fiscal year, if notice of assessment is given to pass-through members within one year from the date of the election.
(8) For purposes of this section, a return filed on or before the last day prescribed by law for the filing of the return shall be considered as filed on such last day, and a return filed after the last day prescribed by law shall be considered as filed on the date that the return is received by the department of revenue.
Source: WI Statutes (Official Site)URL: https://docs.legis.wisconsin.gov/document/statutes/71.77Fetched: 10/7/2026