Assessor's Office

News and Information

Important update: The Assessor’s Office has learned that residents may be receiving notices in the mail encouraging them to file an appeal with a tax agent (for a fee).

Please know that these are legal solicitations that have no affiliation with Boulder County. All residents have the right to hire such paid services or can file an appeal for free through our office.

Assessor’s Office accepts 2026 real property value appeals May 1 through June 8.

Senior Exemption Applications

Please visit the Senior Exemptions page to learn more.

Qualified Senior Primary Residence Applications

Please visit the Senior Exemptions page to learn more.

Qualifying Veteran with a Disability Exemption and Gold Star Spouse Applications

Please visit the Veteran Related Exemptions web page to learn more.

Business Personal Property

Owners of taxable Business Personal Property in Boulder County as of Jan. 1 are required to file a Business Personal Property Declaration every year.
The 2026 deadline to timely file a Business Personal Property Declaration was April 15.
File a Business Personal Property Declaration

Assessor Overview

The Assessor’s Office establishes values every two years for more than 120,000 properties within Boulder County, worth more than $120 billion in market value, using tools such as geographic information systems (GIS) and mass appraisal techniques to perform the appraisal analysis. Property values are used to set tax amounts which the Treasurer’s Office administers and collects.

Connect With Us

• Assessor/Treasurer Change of Address form.
• Ask a question about your Senior Exemption. Applications must be filed by July 15.
• Search for your Notice of Value (NOV) online.