Supervisor of Assessments

*NEW* - Historical information regarding Winnebago County's Equalized Assessed Value can be found at the following links:

The 2019 assessment notices were mailed on August 12th, and publication followed on August 14th & August 15th. Property owners had a little over 30 days from the date of publication to file an assessment complaint with the Winnebago County Board of Review. The deadline for filing 2019 complaints was September 16th, 2019. All complaints must have been either submitted to this office or postmarked by this deadline. Evidence for assessment reduction requests of less than $100,000 is due by October 11th, 2019. Evidence for assessment reduction requests of more than $100,000 is due by October 31st, 2019.

Please click here for a copy of the 2019 Winnebago County Board of Review Rules and Regulations.

Questions about Equalization and how it affects your Property Assessment? Click here.

Main Office: 815-319-4460

Mapping: 815-319-4464

Fax: 815-319-4461

Email: soa@wincoil.us

Supervisor of Assessments Office

404 Elm Street, Room 301

Rockford, IL 61101

Office Hours: Monday through Friday 8:00am - 5:00pm (closed holidays)