Notice of Valuation postcards have been mailed to Boulder County property owners

• Notice of property valuation postcards mailed May 1, 2025.
• Property owners can appeal their values until 11:59 p.m. June 9.
• Questions for Assessor's Office staff can be called in to 303-441-3530.

Boulder County, Colo. - On May 1, 2025, the Boulder County Assessor’s Office mailed all residential property owners a Notice of Valuation postcard that included the property’s basic assessment. The Assessor’s Office would like to remind property owners that those who wish to appeal the determined market value of their home or commercial property are required to file their appeal with the Assessor’s Office by 11:59 p.m. on Monday, June 9.

Property owners may appeal their values on the Boulder County website, by fax, by mail, drop box, or email. There are online tools available at boco.org/AssessorAppeals to help property owners research comparable sales data and attach that information to their appeal.

If you have questions for Assessor’s Office staff, call 303-441-3530. Please leave a voicemail message if you call after hours. Please note that the Assessor’s Office hours are 7:30 a.m. – 5:00 p.m. Monday – Thursday. Bilingual staff are available to help in English and Spanish. Assistance in languages is available through phone interpretation.

Property owners can access a more traditional Notice of Value at BoulderCountyAssessor..Anyone without computer access can call our office at 303-441-3530 to request that a traditional Notice of Value be sent to them at no charge.

State law requires that all real property (land and buildings) in a county be revalued (reappraised) every odd-numbered year. Per state statute, for 2025, the actual value for residential, commercial, industrial, and other property types reflects the market value of the property as of June 30, 2024. The previous biennial reappraisal was done in 2023 based on market values from June 30, 2022.

As area residents are aware, real estate values have held steady as the market slowed. Overall, the median percent change in value for residential properties is –1%. This does not equate to an equal change in property tax.

More information about the relationship between values and property tax can be found on the county’s website: boco.org/2023Valuation

• Contact the Board of County Commissioners
• View the Commissioners' Meeting Documents and Records
• Visit the County Commissioners' webpage

Americans with Disabilities Act Notice

Special Assistance
Boulder County wants to ensure that everyone has equal access to our programs, activities, and services. To request an Americans with Disability Act (ADA) accommodation, please email the ADA Coordinator, or call 303-441-1386. Submit your request as early as possible, and no later than two business days before the event. Boulder County's ADA PoliH3 Heading