Assessor's Office

Valuing Property

    The Assessor’s Office establishes values every two years for more than 120,000 properties, worth nearly $50 billion in market value. The agency uses tools such as geographic information systems (GIS) and mass appraisal techniques to perform appraisal analysis.

    The Assessor discovers and lists information about properties and uses this information to determine property values.

  • Property Assessment Overview
  • How Property Taxes Are Calculated

Appeal Your Real Property Value

Property Information & Mapping

    New online Property Search tool:

  • Works on most mobile devices.
  • Can be used with more web browsers.
  • Makes looking up property information easier.
  • Provides access to more property information.
  • Makes appealing property values online easier.

Senior Tax Exemption

    The Colorado Constitution establishes a property tax exemption for qualifying senior citizens, surviving spouses of senior citizens who previously qualified, and for disabled veterans.

    Deadline: Applications must be filed no later than July 15 to have the exemption apply to your tax bill the following year.

  • Senior Tax Exemption Forms and Instructions

2013 Boulder Flood

    The Boulder County Assessor’s office is working alongside the Land Use department to assess the damage of properties as safely and efficiently as possible. To report property damage caused by the 2013 flood, please contact the Assessor's office by calling 303-441-3530, or by emailing

    More information and resources can be found at Boulder County Flood 2013.

About Business Personal Property

Ask a Question about Your Property

  • Business Personal Property appeals are accepted as on-time June 15 through June 30 each year.
    Ask a question about your business personal property.

Recent Sales

  • Recent Sales Activity—lists of sales for specified time frames. These lists are not intended to be used for real property assessment appeals.

Information Collection

The Assessor’s Office gathers and maintains information on properties, including:

  • Ownership
  • Location
  • Use
  • Sales
  • Building measurements
  • Construction type
  • Construction costs
  • Rental income, if applicable

Sources for this information are:

  • Real property deeds and declarations
  • Subdivision maps
  • Building permits
  • Local building contractors
  • Property owners
  • Declarations filed by owners of taxable personal property
  • Onsite inspections by staff

Learn more about:

Assessor Logo

Jerry Roberts, Assessor

Jerry Roberts

Meet the Assessor

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Main: 303-441-3530
Alternate: 303-441-4830
Fax: 303-441-4996
Mailing Address
Main: PO Box 471
Boulder, CO 80306-0471
Business Personal Property
Main: 303-441-3316
Fax: 303-441-1783
Mailing Address
PO Box 1759
Boulder, CO 80306-1759


1325 Pearl St., 2nd floor
Boulder, CO 80302
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1376 Miners Dr., Unit 105
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