WI · 2026 appeal calendar

Wisconsin Property Tax Appeal Deadlines 2026.

Wisconsin property tax appeal deadlines and filing windows for commercial real estate. Verify with your local assessor or appeal board for the specific jurisdiction before filing.

Updated May 2026

Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.

2026 appeal calendar

Wisconsin deadlines at a glance.

State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.

Month Type Event Date Details
May RP
Appeal Deadline
May-Oct After an informal review by the local assessor, review may be sought with the board of review, which meets for 30 days beginning on the 2nd Monday of May (3rd Monday of May in Milwaukee and Madison). Written or oral notice to the clerk is required at least 48 hours prior to the scheduled meeting. Written complaints to the Department of Revenue must be filed either within 20 days after receipt of the board's determination notice or within 30 days of the date specified on the affidavit if no notice is received. Appeals to thestate tax commission must be filed within 60 days of the determination.

RP = Real Property · BPP = Business Personal Property · Both = Applies to both

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