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 Information and Mapping
Sales Search
Property Value Appeals
Appeals for Real Property were accepted from May 1 through June 1.
The Assessor will mail Notices of Determination on real property appeals on or before August 31.
If the property owner filed an appeal during May, and disagrees with the Assessor's Determination, then they may appeal the decision in writing to the County Board of Equalization (BOE) on or before September 15.
- Real Property Appeals Process
- Notice of Valuation
- Appeals Calendar
- Board of Equalization (BOE)
Ask a Question about Your Property
- Real Property appeals were accepted as on-time May 1 through June 1.
Ask a question about your real property.
- Business Personal Property appeals were accepted as on-time June 15 through June 30.
Ask a question about your business personal property.
Fourmile Canyon Fire
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 News
Find the latest news and events from the Assessor's Office.
The Boulder County Assessor’s Office has received many awards, such as:
National Association of Counties (NACo) Achievement Award
- Denver Regional Council of Governments (DRCOG) Exemplary Government Award
- International Association of Assessing Officers (IAAO) Distinguished Assessment Jurisdiction
- ESRI Special Achievement in GIS recognition
Please send us any comments or suggestions you may have.