Overview
Property value is the dollar-value placed on land and buildings for the purposes of administering property taxes.
The two commonly-used methods of valuing property in Wisconsin are "assessed" and "equalized." Assessed valuation is property value as determined by the local municipal assessor on January 1 in any given year. Equalized valuation results when the Department of Revenue (DOR) applies an adjustment factor to the assessed value. The adjustment factor incorporates, among other elements, actual property sales in the municipality during the past year and is meant to ensure each type of property has comparable value regardless of local assessment practices.
Fair Market Value
Most state computations use equalized value, otherwise known as "fair market" value. Fair market value can be further defined as the value that would be agreed upon between a willing buyer and a willing seller in an "arm's length" transaction where neither is required to act.
New-Year Information
The first-time school districts receive the new year information in an official value certification is in October. The October 1 Tax Apportionment Value Certification is used to apportion levies and determine municipal tax bills. After October 1, DOR may refine this same set of numbers until a "final" version is issued the following May (almost 1 1/2 years after the original assessment). This final version is known as the School Aid Value Certification and will be used in the FOLLOWING year's Equalization Aid formula. So, as an example, property value as of January 1, 2026, will eventually be used in the 2027-28 Equalization Aid computation.
It is important that districts understand which values are used for what computations.
Resources
- Glossary of Finance Terms (further information on property valuation, including a discussion of the Tax Incremental Finance TIF Increment)
- Property Valuation - Longitudinal Data Information and resources associated with past fiscal school years.
Fiscal School Years
2025-26 School Fiscal Year
- Fall School District Certification of 2025 Values - Tax Apportionment - These values are used to set school levies for the 2025-26 school year.
- Fall School District Certification of 2025 Values - Tax Apportionment. - These values are used to set school levies for the 2025-26 school year. Note: Please pay attention to the column headers.
- Spring School District Certification of 2024 Values by District - School Aid - with reorgs These values, adjusted for any reorganization orders effective July 1, 2025, are used in the October 15, 2025, certification of school district equalization aid eligibility.
- Spring School District Certification of 2024 Values by Municipality - School Aid - with reorgs