Commercial & Business Property
Wisconsin Commercial Property Tax Appeals
Office, retail, industrial, multifamily, and special-purpose buildings in Wisconsin are frequently over-assessed. Here's how commercial assessments work, the deadline to challenge yours, and what it takes to win.
How commercial is assessed
Wisconsin assesses toward full (market) value. The Open Book period lets commercial owners discuss the value informally with the assessor before the Board of Review.
Burden of proof
The property owner (or their authorized agent) bears the burden of proving the assessment exceeds market value. The assessor's value is presumed correct until rebutted with credible evidence.
Key to a Wisconsin commercial appeal: Open Book before the Board of Review
You must attend Open Book or file a written objection to preserve rights; a recent sale or income analysis presented then often resolves commercial values before a formal hearing.
Wisconsin Filing Deadline & Where to File
File With
Board of Review
Deadline
First meeting of Board of Review (varies by municipality, typically May–June)
Window Opens
After assessment roll is open for examination (typically May–June)
Typical Duration
1–3 months
Wisconsin's Open Book period allows informal discussion with assessor before formal Board of Review. Must attend Open Book or file written objection. Can appeal to circuit court within 90 days.
⚠️ Deadlines vary by county/municipality in Wisconsin. Confirm the exact date for your property's jurisdiction before filing.
How commercial value is proven
Income-producing commercial property is usually valued by capitalizing net operating income (NOI ÷ market cap rate). The strongest appeals come with a clean rent roll, a trailing-12-month operating statement, current vacancy, and market cap-rate support. Where the property is owner-occupied or special-purpose, the cost and sales-comparison approaches carry more weight.
Evidence that wins a commercial appeal
- Current rent roll and a trailing-12-month operating statement
- Actual vacancy and collection loss (vs the assessor's stabilized assumption)
- Market capitalization rate support for the property type and submarket
- Recent arm's-length sales of comparable commercial buildings
- Evidence of physical, functional, or economic obsolescence
- Any change in use, tenancy, or condition since the assessment date
How to appeal a commercial assessment in Wisconsin
- 1Pull the assessment — confirm the assessed value, the assessment ratio/class, and how the assessor derived it (income, cost, or sales).
- 2Build the valuation — capitalize actual net operating income and gather comparable sales to establish market value as of the assessment date.
- 3File before the deadline — submit to Board of Review by First meeting of Board of Review (varies by municipality, typically May–June), with the authorization signed by someone able to bind the owning entity.
- 4Present at the hearing — commercial hearings are evidence-driven; a clean income approach and credible comps carry the day.
Think your Wisconsin commercial property is over-assessed?
We pull the assessment, build the income-approach case, and file the appeal. Fee: 20% of first-year savings — only if we win. Nothing upfront, and the reduction can hold for years.
Related resources
Assessment ratios, class rates, and deadlines in Wisconsin are set by statute and can change year to year, and often vary by county or municipality. Verify current figures and dates with your county assessor or clerk of the board before filing. This page is general information, not legal or tax advice. TaxedFairly is a product of WebLab LLC.