Under Colorado law, all real property (land, buildings, improvements, etc.) must be re-appraised every two years. This occurs in each odd-numbered year (2021, 2023, etc.). The Assessor Department studies the prices of properties which sold during the 24-month period ending on June 30 of the year prior to the reappraisal. For example, the new 2023 values are based on properties which sold between July 1, 2020 and June 30, 2022, and based on what was there as of January 1, 2023 (assessment date).
New values are set each year for business personal property owned by businesses based on the information annually submitted by the taxpayers on personal property declarations.