Assessment Ratio
6.55%
Protest Deadline
June 1, 2026
Official Form
Real Property Appeal
Risk of Increase
No
How Assessment Works in Colorado
Colorado assesses residential property at 6.55% of actual (market) value. Commercial property is assessed at 29%. Your tax bill is based on the assessed value (6.55% of market value), not the full market value. The residential rate is set by the legislature and can change.
How to File in Colorado
File with your county assessor by mail, in person, or online (where available). The deadline is June 1 for the current reassessment year.
Step-by-Step
Colorado Protest Process
Receive your Notice of Valuation from the county assessor (mailed by May 1 in reassessment years).
File a protest with the county assessor by June 1.
The assessor reviews your evidence and issues a Notice of Determination.
If not satisfied, appeal to the county Board of Equalization within 30 days.
If still unresolved, appeal to the Board of Assessment Appeals (BAA) or district court.
FAQ
Colorado Property Tax Protest Questions
Can my Colorado assessment increase during a protest?
No. Colorado law prohibits the assessor from increasing your value during the protest process. Your value can only stay the same or go down.
How does the 6.55% ratio work?
If your home has a market value of $500,000, the assessed value is $32,750 (6.55%). Your tax bill is this assessed value multiplied by your mill levy. If the county overvalues your home at $550,000, you pay taxes on $36,025 instead of $32,750.
How often does Colorado reassess properties?
Colorado reassesses all property every two years (biennial cycle). The most recent reassessment used a June 30, 2024 valuation date. You can only protest in the reassessment year or if there's a change in your property.