Wisconsin PTET 2026: deadline, rate, who can elect
Wisconsin (WI), tax year 2026, from the same rules the connector returns. Last verified October 24, 2026.
Informational. Not tax advice.
Elective PTET
Yes
A partnership, an LLC treated as a partnership, or a tax-option S corporation may elect to pay tax at the entity level.
Who can elect
A partnership or an LLC treated as a partnership, and a tax-option S corporation. The partnership needs consent from partners who together hold more than 50 percent of the capital and profits. The S corporation needs consent from shareholders who together hold more than 50 percent of the shares.
The two 2025 instruction booklets are the sources.
How the election is made
A partnership checks box I on Form 3. An S corporation makes the election on Form 5S. Either election may be revoked on an amended return filed by the extended due date, with the same more-than-50-percent consent.
The instructions say the election is made when the return is filed.
Election deadline
On or before the extended due date of Form 3 for a partnership, or the extended due date of Form 5S for an S corporation.
The 2025 instructions state the deadline as an each-year rule. They do not give a 2026 calendar date.
Rate
Section 71.21(6)(a) taxes an electing partnership at 7.9 percent of net income reportable to Wisconsin. Section 71.365(4m)(a) taxes an electing tax-option S corporation at the same 7.9 percent. The 2026 Form 3-ES instructions multiply estimated Wisconsin business income by 7.9 percent for a partnership taxable year that begins in 2026.
Neither statute paragraph limits the 7.9 percent rate to an earlier year.
Owner relief
Partners and shareholders do not include in Wisconsin adjusted gross income the share of items that the electing entity reports. The entity's net income is taxed to the entity.
The instructions describe an exclusion from the owner's Wisconsin adjusted gross income, not a credit.
Estimates
A partnership that elects under section 71.21(6)(a) for a taxable year beginning in 2026 uses the 2026 Form 3-ES unless section 71.09(11) applies. The first payment is generally due the 15th day of the 4th month of the taxable year and equals one quarter of the estimated tax. For a calendar-year partnership that first meets the requirement after March 31, the instructions state June 15, 2026 (50 percent), September 15, 2026 (75 percent), and January 15, 2027 (100 percent). Section 71.365(4m)(d)4 says sections 71.29 and 71.84 apply to an electing tax-option corporation for a taxable year beginning in 2019 and later. That paragraph does not state the installment dates.
The 2026 Form 3-ES states the partnership dates. The S corporation statute incorporates sections 71.29 and 71.84 without stating dates.
Sunset or repeal
Sections 71.21(6) and 71.365(4m) do not state an end date for the election.
Both subsections were read through the Department's authority to promulgate rules.
Sources for this year
- Wisconsin Department of Revenue, 2025 Schedule 3-ET instructions
- Wisconsin Department of Revenue, 2025 Schedule 5S-ET instructions
- Wisconsin Legislature, section 71.21(6)(a)
- Wisconsin Legislature, section 71.365(4m)(a)
- Wisconsin Department of Revenue, 2026 Form 3-ES instructions
- Wisconsin Statutes § 71.01(6)
- Wisconsin Statutes § 71.22(4)
- Wisconsin Statutes § 71.98
Bonus-depreciation conformity is on its own page.