If you own a home in the Denver Metro or Front Range area, you know that property tax assessments have been a hot-button issue lately. The 2025 reappraisal set values based on market conditions as of June 30, 2024. 2026 is an intervening year, and some owners won’t receive a Notice of Valuation unless something changes — but the right to protest remains.
Here is exactly how the process works and how a professional appraisal from VolkHaus can help.
1. Know the Deadline
In Colorado, County Assessors mail Notices of Valuation (NOV) around May 1st. You have a narrow window — typically until June 8th — to file a formal protest. Miss it and your options shrink dramatically. Always confirm your county’s posted deadline for the current year.
2. Understand the Data Window
For the 2026–2027 tax years, the County Assessor isn’t looking at what your home is worth today. They’re looking at a specific base period ending June 30, 2024. Your evidence should focus on sales from that study period. Sales after June 30, 2024 carry less weight because they reflect a later market.
3. Mass Appraisal vs. Professional Appraisal
The county uses a mass appraisal system — a computer algorithm that looks at your neighborhood as a whole. It doesn’t know your neighbor’s house was fully renovated while yours still has the original 1990s kitchen, or that your property backs up to a noisy road.
A professional appraiser does what the algorithm can’t. We physically inspect your specific property, select the most accurate comparables from the correct base period, and deliver a defensible report aligned with the county’s valuation date.
4. How to File Your Protest
File online through your county assessor’s website — Denver, Jefferson, Adams, Boulder, and most Front Range counties all have online portals. Attach evidence. A Zestimate won’t cut it. An independent appraisal report is the gold standard.
The Bottom Line
Don’t wait until June 7th to start. If your Notice of Valuation looks high, contact us early — (720) 432-0474 or charles@volkhaus.com — so we have time to build a well-supported case.