News and Information
The Assessor’s Office at the historic courthouse in Boulder (1325 Pearl St.) will be closed on Thursday, Dec. 18 due to loss of power at the building from the wind event. Residents can reach staff for assistance by phone at 303-441-3530 or by email to assessor@bouldercounty.gov.
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 is April 15.
File a Business Personal Property Declaration
Real Property
Real Property Value Appeals will be accepted May 1 through June 8, 2026
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 Business Personal Property. Appeals are accepted June 15–30 each year.
- Ask a question about your Real Property. Appeals are accepted May 1–June 9 each year.
- Ask a question about your Senior Exemption. Applications must be filed by July 15.
- Search for your Notice of Value (NOV) online.
