Colorado Property Tax Appeal & Protest Guide (2026)
Calculate your assessment reduction, check the June 8 (postmark deadline for assessor protest following May 1 Notice of Valuation) statutory deadline, and access county appraisal district e-File portals under C.R.S. § 39-8-106
Colorado Assessment Appeal Standard: Under C.R.S. § 39-8-106, homeowners in Colorado can appeal county real property assessments through the Assessor Notice of Protest (May 1 – June 8) or County Board of Equalization (CBOE) appeal (by July 15). The statutory appeal deadline is June 8 (postmark deadline for assessor protest following May 1 Notice of Valuation) using form Real Property Notice of Valuation & Protest Form. Protests are evaluated on Overvaluation based on 24-month study period data and Improper residential assessment rate application (currently ~6.7% - 7.15%) supported by Comparable sales strictly from within statutory 24-month base period ending June 30 of prior even year and Square footage verification.
Colorado Property Tax Appeal & Protest Calculator
Governing Law: C.R.S. § 39-8-106 · Annual Deadline: June 8 (postmark deadline for assessor protest following May 1 Notice of Valuation)
1. Property Assessment & Target Valuation
Enter the preliminary appraised value from your county assessment notice and the realistic fair market value supported by comparable sales.
2. Local Tax Rate & Jurisdiction
Property tax rates are set by combined county, city, ISD, and special hospital/MUD districts.
Reducing your assessed valuation by $55,000 lowers your annual tax liability across all local taxing entities (school district, county, city, hospital).
⚖️ Statutory Protest Stages in Colorado:
- Assessor Notice of Protest (May 1 – June 8)
- County Board of Equalization (CBOE) appeal (by July 15)
- Board of Assessment Appeals (BAA), Binding Arbitration, or District Court
COUNTY PROPERTY TAX APPEAL EVIDENCE DOSSIER & HEARING PACKET
JURISDICTION: STATE OF COLORADO · STATUTE: C.R.S. § 39-8-106
Target Tax Year: 2026 · Official Protest Instrument: Real Property Notice of Valuation & Protest Form
Filing Deadline: June 8 (postmark deadline for assessor protest following May 1 Notice of Valuation)
Prepared: 10/23/2026
| County Preliminary Appraised Value: | $420,000 |
| Claimant Target Market Value (Supported by Comps): | $365,000 |
| Combined Effective Local Tax Rate: | 1.65% |
| Estimated Annual Tax Overcharge Savings: | $908 / Year |
1. Comparable Market Sales (Comps) Grid — Valuation Equity Evidence
| Subject Property / Comps | Living Area (Sq Ft) | Sale Date | Sale / Assessed Price | Adjusted Price / Sq Ft |
|---|---|---|---|---|
| Subject Property (County Valuation) | — | Lien Date: Jan 1 | $420,000 | — |
| Comp 1: Same Subdivision / Block | Similar GLA | Past 12 Months | — | — |
| Comp 2: Similar Model / Age | Similar GLA | Past 12 Months | — | — |
| Comp 3: Similar Bed/Bath Count | Similar GLA | Past 12 Months | — | — |
*Attach county deed records, MLS closing settlement statements, or appraisal district property cards for each comparable sale.
2. Itemized Deferred Maintenance & Physical Condition Deductions
| Defect / Condition Issue | Evidence Attached | Estimated Repair Cost |
|---|---|---|
| Roof / Plumbing / Foundation | Contractor written repair estimate + photos | $_______________ |
| HVAC Mechanical End-of-Life | HVAC diagnostic inspection report | $_______________ |
| Negative Externalities (Traffic / Drainage) | Site photos, aerial GIS map, flood zone record | $_______________ |
3. Appraisal Review Board (ARB) 5-Step Hearing Strategy:
- Collate 4 Copies: Hand 1 copy to each of the 3 panel members and 1 copy to the county appraiser.
- Focus on Facts, Not Taxes: State tax boards have zero control over tax rates; frame arguments strictly on Fair Market Value and Uniform Assessment Equity.
- Stick to the Lien Date: Only cite market transactions and physical condition occurring on or before the statutory valuation date.
- Present Contractor Estimates: Unrepaired physical defects must be supported by third-party licensed bids.
- Politely Rebut County Comps: Point out superior upgrades, square footage variances, or busy road differences in county comps.
Property Owner / Appellant Signature:
Printed Name / Executed Under Penalty of False Swearing / Date
County Property Identification / Account #:
Geographic ID / Parcel Number / Subdivision Lot & Block
Colorado Property Tax Protest Legal Framework
Statutory Authority & Deadlines
Statutory Appeal Stages
- Assessor Notice of Protest (May 1 – June 8)
- County Board of Equalization (CBOE) appeal (by July 15)
- Board of Assessment Appeals (BAA), Binding Arbitration, or District Court
Mandatory Evidence Checklist
- Comparable sales strictly from within statutory 24-month base period ending June 30 of prior even year
- Square footage verification
- Condition adjustment photographic evidence
Protest Benchmarks
Frequently Asked Questions
What is the property tax appeal deadline in Colorado for 2026?
What are the legal grounds for protest in Colorado?
Who carries the burden of proof in a Colorado property tax hearing?
What form must I file to initiate an appeal in Colorado?
What is the historical success rate for residential property protests in Colorado?
Official Standards & Authoritative Sources
Colorado Division of Property Taxation (DPT)
Colorado Official Property Tax Rules & Oversight
official-state-agencyReviewed & verified by the RateFig Property Tax & Assessment Editorial Team. Data retrieved October 19, 2026. Estimates are planning aids, not financial advice — see our editorial standards.
Related tools from our network
A focused set of free calculators and guides across related topics — no account required.