Is Your Commercial Property Over-Assessed?

 Posted on March 03, 2026 in Property Tax

What Milwaukee Commercial Property Owners Must Know About the 2026 Assessment Cycle and Board of Review Appeal Deadline

Milwaukee Property Tax Litigation | February 2026

For owners of commercial, industrial, and multi-family investment property in Wisconsin, the 2026 assessment cycle is already in motion. With assessment notices arriving this spring, the window to challenge an over-assessment is narrow — and missing it can mean years of inflated tax liability with no recourse.

Every percentage point of over-assessment on a commercial property represents real dollars — often tens of thousands annually on a single asset. Unlike residential homeowners, commercial property owners frequently hold properties where even a modest reduction in assessed value generates substantial, recurring tax savings. And yet, most over-assessments go unchallenged simply because owners are unaware of the process or miss the deadlines.

At Mallery S.C., our property tax attorneys work exclusively with commercial property owners, investors, developers, and landlords to identify over-assessed properties, build evidence-based challenges, and represent our clients through every stage of the Wisconsin appeal process. Here is what you need to know for 2026.

How Wisconsin Assesses Commercial Property

• Income Approach — the income capitalization approach (particularly important for income-producing properties such as office, retail, industrial, and apartment buildings);
• Sales Approach — the sales comparison approach (based on comparable market transactions); and
• Cost Approach — the cost approach (replacement cost less depreciation).

In practice, Wisconsin assessors often rely too heavily on the cost approach or use stale comparable sales that fail to capture current market conditions. For income-producing properties, an assessor who ignores the income approach or uses inflated cap rates, incorrect vacancy assumptions, or above-market expense ratios can produce a drastically inflated assessed value.

Commercial property values are also highly sensitive to lease terms, tenant credit, physical condition, market absorption, and environmental considerations. These are just some of the nuances that mass appraisal techniques frequently miss. Properties that have experienced increased vacancy, declining rents, capital expenditure requirements, or other value-impacting events since the prior assessment should be especially attuned to finding these potential oversights.

2026 Key Dates for Milwaukee Commercial Property Owners

The following timeline applies to most Wisconsin municipalities, including Milwaukee. Specific dates for Open Book and Board of Review hearings are set locally and will be published by the City of Milwaukee Assessor's Office.

The Board of Review Appeal: What Commercial Owners Need to Know

Filing a Written Objection

To preserve your appeal rights, a written objection must be filed with the municipal clerk on or before the deadline set by the Board of Review. In Wisconsin, objection forms are generally available online at the Wisconsin Department of Revenue. The objection must identify the property and state the grounds for your challenge. Filing early and correctly is essential.

Unlike a residential appeal, a commercial property challenge typically requires substantial supporting documentation from the outset. Submitting a bare-bones objection without evidentiary support may technically preserve your rights but will limit your effectiveness at the hearing.

Building Your Evidentiary Case

The Wisconsin Supreme Court has established that the assessor's value is presumed correct, and the burden falls on the property owner to produce sufficient credible evidence of a different value. For commercial properties, this almost always requires a formal appraisal by a qualified, Wisconsin-certified commercial appraiser.

Compelling evidence in a commercial BOR hearing includes:

• An MAI-designated commercial appraisal applying appropriate valuation methodology for the property type
• Certified rent rolls, rent concession schedules, and lease abstracts demonstrating actual income
• Vacancy and collection loss data benchmarked against submarket absorption rates
• Evidence of deferred maintenance, environmental issues, or functional obsolescence reducing value
• Arm's-length comparable sales of similar commercial properties in the relevant market area
• Market-derived capitalization rates supported by investor surveys and transaction data

The strength of your presentation before the Board of Review directly affects not only the outcome at the BOR level, but also the quality of the record for any subsequent circuit court appeal.

Depending on the case, presenting at the Board of Review often has limited value. In those cases, it may be appropriate to seek a waiver of the Board of Review hearing in order to directly bring the claim in Wisconsin Circuit Court.

The Board of Review Hearing

The BOR is typically composed of local officials who volunteer and are appointed. Generally, they are not professional real estate appraisers or attorneys. Presentations must be clear, well-organized, and persuasive to a non-expert audience. The hearing is quasi-judicial: you may present witnesses and documentary evidence, cross-examine the assessor's witnesses, and make legal arguments.

Having experienced legal counsel at your BOR hearing is not a luxury for commercial property owners. It is a strategic necessity. Attorneys familiar with Wisconsin property tax law know how to structure the evidentiary record, counter the assessor's methodology, and preserve issues for appeal. Moreover, challenging your assessment is an adversary proceeding. The assessor is likely to have an attorney there to assist in attacking your appeal and looking for procedural reasons to dismiss your appeal before it even gets to the actual Board of Review hearing itself.

After the BOR: Circuit Court Options

If the BOR does not provide adequate relief, commercial property owners have two primary avenues for further appeal under Wisconsin law:

• Wis. Stat. § 70.47(13): Writ of Certiorari — Filed in Milwaukee County Circuit Court within 90 days of the BOR's written decision. The court reviews whether the BOR acted according to law, not whether it reached the right value. The circuit court review is limited to interpreting the record presented at the BOR.
• Wis. Stat. § 74.37: Tax Refund Action — Allows a de novo (full) review of the valuation question, without being bound by the BOR's factual record. Particularly valuable when new valuation evidence is available.

Mallery s.c counsels commercial property owners on this decision every year.

The Commercial Property Tax Stakes: A Quick Illustration

Consider a Milwaukee office building assessed at $8,000,000. Assuming a combined effective tax rate of approximately 2.3% (Milwaukee's rate in recent years), the annual property tax burden is roughly $184,000. If a qualified appraisal establishes a fair market value of $6,500,000, then the corrected annual tax liability would be approximately $149,500. That is a savings of over $34,000 per year, and a cumulative benefit of $100,000 or more over a typical appeal cycle.

The calculus is similar for industrial, retail, and multi-family investment properties. The cost of a qualified appraisal and legal representation is typically a fraction of the potential tax savings, which savings would recur year after year if the corrected assessment is maintained.

Property tax over-assessments compound silently. A commercial property owner who does not appeal in 2026 locks in the higher tax burden for the entire year and has no mechanism for retroactive relief once the appeal window closes.

Why Mallery is Right for Your Commercial Property Tax Appeal

Mallery’s property tax litigation team has represented commercial property owners, real estate investors, developers, REITs, and corporate occupiers in Wisconsin property tax matters across the state. Our property tax practice is built on a foundation of commercial real estate expertise, rigorous valuation analysis, and a track record of results before local Boards of Review and Wisconsin courts.

• Deep Milwaukee market knowledge — We understand local assessment practices, assessor methodologies, and BOR procedures specific to Milwaukee and surrounding municipalities.
• Commercial valuation expertise — We work with leading MAI-certified commercial appraisers and can evaluate whether your current assessment reflects market reality.
• Full-service representation — From Open Book through circuit court, we handle every stage of the process so you can focus on managing your portfolio.

Time is the one resource you cannot recover in a property tax appeal. If your 2026 notice arrives and the value does not reflect market reality, act immediately and contact one of the lawyers on the commercial property tax team immediately.

Attorney Christopher L. Strohbehn 

Attorney Russell J. Karnes  

Attorney Hannah E. Rodriguez