City assessor outlines 2025 revaluation; citywide taxable value up about $1.8 billion

Sam Walker, the city assessor, told the Waukesha Common Council on April 15 that the 2025 citywide revaluation increased total assessed market value by about $1.8 billion, or roughly 20.63%, bringing the city's assessed value to about $10.5 billion from approximately $8.7 billion before the revaluation.

Walker said the revaluation used 2024 valid property sales and that notices of change in assessment would be mailed on April 25. The open-book review period will run April 28'May 16 and the initial Board of Review session is scheduled for June 6. Walker also said manufacturing values will not be available until later in the year, and that tax-rate impacts will not be known until budgets, net new construction and manufacturing values are finalized.

Why it matters: Walker said the city must stay within the state-required assessment ratio range (about 90% to 110% of market value). Without a 2025 revaluation, he said the city's assessment ratio would have been about 85%, out of compliance, and that delaying another two years would risk a repeat of the large adjustment seen in 2023.

Walker discussed methodology and differences by property type. Residential values increased by an average of about 14% (market-change estimate for all residential properties about 16% for the sold sample), while commercial values rose faster'about 39% on the full-population estimate and roughly 47% for the sold-sample measure. Walker said commercial property owners bear the heavier share of the increase in this cycle.

Walker described an expanded cleanup review for 2025: staff examined every residential property that changed by more than 25% to identify causes (sales, building permits, previously unrecorded improvements or neighborhood outliers) and applied neighborhood adjustments where needed to avoid major outliers. Condominiums were reviewed by complex.

Walker said 22,915 parcels were valued for the revaluation; manufacturing class values are pending and were excluded from the initial totals. He also said the assessment notice package had been expanded to four pages with contact information, QR links to revaluation materials and guidance for taxpayers who wish to appeal.

Council members asked clarifying questions. Alder Mike Anderson asked what constitutes a "valid sale;" Walker answered that this means an arm's-length transaction (not a sheriff sale, a sale under duress or an intra-company/family transfer). Alder Anderson also asked whether some properties decreased; Walker confirmed there were pockets with decreases and that staff adjusted values where the data indicated a decline.

Walker repeatedly cautioned that assessments are only one factor in property-tax bills and that tax-rate impacts will be determined later, after budget approvals and the state's reporting of net new construction and manufacturing values.

Looking ahead: Notices go out April 25, open-book sessions are April 28'May 16 and the initial Board of Review is June 6. Walker encouraged taxpayers with questions to contact the assessor's office and said appeals are welcome as a source of data correction.