Level 2 Fire Restrictions in effect for western areas of Boulder County. No fireworks, fires, open flame, or shooting (see map and flyer).

Many County services are being offered online. Additionally, a variety of resources are available for those impacted by COVID-19.

Assessor’s Office

Assessor's Office

News & Information

Assessor’s Office Status

coronavirus imageAll Assessor’s Office locations (the main location in Boulder as well as remote offices in Longmont and Lafayette) are closed to walk-in traffic until further notice.

Staff are available online and by phone during regular business hours to take your questions or schedule appointments. Please call 303-441-3530, or email Assessor@BoulderCounty.org.

Senior Homestead Property Tax Exemption

The Colorado Constitution establishes a property tax exemption for qualifying older adults, surviving spouses of those who previously qualified, and for disabled veterans. Applications must be filed no later than July 15 for the exemption to apply to your tax bill next year.

Applications must be postmarked by July 15 to be on time. To ensure your application is delivered on time Senior exemptions can be dropped off at:

  • Boulder: Downtown Boulder Courthouse Complex, 1325 Pearl Street. Use the mail slot on the Treasurer’s Office door on the east side of the main (middle) building of the 3-building complex.
  • Longmont: St. Vrain Community Hub, 515 Coffman Street. Use the HHS drop box on the west entrance (Terry St. side) of the building.

Property Value Appeals were accepted May 1 through June 1, 2020

The Assessor’s Office will mail Notices of Determination to property owners who file on-time appeals on or before September 16, 2020. Property owners will have until September 28, 2020 to appeal their determination to the Board of Equalization.

Ask a question about your Real Property

Treasurer’s Tax Payment Delay Policy

Services and Information


The Assessor’s Office establishes values every two years for more than 120,000 properties within Boulder County, worth nearly $50 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

Contact Us

Due to COVID-19, all Assessors Office sites are closed for business until Sunday, May 31. Please call or email us with your questions during our normal business hours.

Phone: 303-441-3530
Fax: 303-441-4996

Business Personal Property
Phone: 303-441-3316
Fax: 303-441-1783


Schedule a meeting

Mailing Address
Main: PO Box 471
Boulder, CO 80306-0471

1325 Pearl St., 2nd floor
Boulder, CO 80302
Map & Directions
Hours: 8 a.m.-4:30 p.m. M-F

515 Coffman Street, Suite 114
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1376 Miners Dr., Unit 105
Map & Directions