Rock County, Wisconsin Tax Assessors' Office

Where is the Rock County Tax Assessor's Office?

While many counties have county-wide tax assessors, Rock County has one cities and towns with their own local tax assessors. If your property is located within any of these localities, see that page for your tax assessor's contact information.

What can the Rock County Assessor's Office do for me?

The Rock County Tax Assessor's Office oversees the appraisal and assessment of properties as well as the billing and collection of property taxes for all taxable real estate located in Rock County.

Contact the assessor's office if you need help with paying your property taxes, applying for a homestead exemption or other tax exemption, reporting upgrades to your home, appealing your property tax assessment, or verifying your property records.

Submitting a Rock County property tax appeal

If you believe that your house has been unfairly overappraised (i.e. appraised at a value higher than the true market value of the property), you can attempt to get your home re-appraised at a lower value by contacting the Assessor's Office to submit a property tax appeal.

You will have to submit a form describing your property and sufficient proof that it is overassessed, including valuations of similar homes nearby as evidence. If your appeal is accepted, your home assessment (and property taxes) will be lowered as a result.

If you would like to appeal your property, call the Rock County Assessor's Office at (608) 757 5610 and ask for a property tax appeal form. Keep in mind that property tax appeals are generally only accepted in a 1-3 month window each year.

For more information and example appeals, see how to appeal your property taxes.

How can I contact Rock County?

You can try contacting the Rock County local government directly with any issues the Assessor's Office can't solve. In many counties, certain property records such as deeds are kept in the county courthouse or county archives instead of at the tax assessors' office.

The county seat for Rock County is located in the County Courthouse in Janesville, which is where the Rock County Assessors' Office is also located. You can direct your general inquiries to Rock County with the contact info listed below.

Rock County Phone Number

608-757-5660

Rock County Fax Number

608-757-5511

Rock County County Courthouse Address

County Courthouse
51 S Main St
Janesville, WI 53545-3951

Useful Rock County Links:

• Property Tax Search Tool & GIS Map
• Pay Your Property Tax
• Rock County Government Homepage
• Rock County Assessors' Office Homepage
• GIS Map & Parcel Search
• City of Janesville - Property Tax Search
• Rock County View by municipality