Property Assessment Data XML File

January 23, 2024

To: Certified Assessors, Public Assessor List
County Real Property Listers, Treasurers, Clerks, Registers of Deeds
Municipal Clerks and Treasurers

The Wisconsin Department of Revenue (DOR) recently expanded our XML assessment and tax roll web page to include an XML standard data file for property assessment information.

Property Assessment Information

  • Assessors discover property assessment information, then use it to list each property, and finally determine each property's taxable value
  • Assessors are required to provide the municipality with two versions of the municipality's property assessment data:
    1. The format native to the assessment software
    2. A non-proprietary format (comma delimited text, MS-Access, DB2, SQL, XML)
  • See Chapters 7 and 8 of the Wisconsin Property Assessment Manual for additional information

XML Property Assessment Data File (Schema) Development

  • Assessors, municipalities and counties have requested DOR provide a standard statewide assessment data file
  • XML is the nonproprietary format of the property assessment data file
    • XML format satisfies the requirement for assessors to provide municipalities with a non-proprietary format of the municipality's assessment data
    • XML format is consistent with the XML property assessment and property tax roll schema currently used by Wisconsin local governments and Wisconsin property assessment and taxation software vendors
  • Property assessment data file schema was developed in coordination with assessment software vendors that provide services to assessors in Wisconsin. The schema applies the:
    • Standards and codes found in the Wisconsin Property Assessment Manual Vol I and Vol II
    • Recommendations from Wisconsin assessment software vendors

Goals

  • Short term – obtain XML schema complaint property assessment data files from Wisconsin assessment software vendors
  • Long term – assessors, municipalities and counties are able to exchange parcel data in a standard non-proprietary format

Steps – DOR:

  • Provided the 2024 property assessment data file XML schema to Wisconsin assessment software vendors
  • Asked each vendor to provide sample files for each property class to determine whether the vendor's system generates a compliant XML parcel data file
  • Will post the vendors, that provide a compliant XML parcel data file, on our website (see the "Parcel Data Electronic File Transmissions" on the web page)
    • Assessors – consider using assessment software that produces compliant XML property assessment data files
    • Municipalities – consider assessment contracts that require use of an assessment software producing complaint XML property assessment data files (See the Property Assessment Guide for Municipal Officials for sample contracts)​
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