Douglas County sets May 1 deadline for property valuation appeals

Douglas County property owners who believe their valuations are too high have a short window to act: real-property appeals open May 1 and close June 8, and anything left unchallenged can flow into tax bills, mortgage escrow estimates and household budgets.

The Assessor’s Office says only properties with a change in value, a change in use or a change in ownership received Notices of Value this year, about 10% of county property owners. That means some homeowners will not be waiting for a letter at all. If a property changed in one of those ways, or if the notice looks wrong, the time to review it is now.

Douglas County says the appeal process starts with the appraisal date, which for the 2025 reappraisal was June 30, 2024. For the 2025 and 2026 tax years, the county used a 24-month sales study period from July 1, 2022, through June 30, 2024, and analyzed more than 16,000 residential sales to make its time-trend adjustments. The county’s own guidance says owners should check square footage, lot size, garage and basement details, construction materials and comparable neighborhood sales from that period before filing.

Appeals for real property can be submitted online until midnight on June 8, or mailed as long as they are postmarked by that date. The county also encourages in-person meetings by appointment at the Wilcox Building in Castle Rock. Business personal-property appeals begin June 15 and must be delivered or postmarked by June 30.

The county says property values and tax bills are not the same issue. If the valuation looks right but the tax bill still seems too high, the fix is with the taxing authorities that set mill levies and budgets, not with the Assessor’s Office. If a taxpayer loses at the assessor level, the next step is the Douglas County Board of Equalization, where the Board of County Commissioners sits.

Toby Damisch has said the 2025 cycle brought relief after the sharp increases seen in 2023, and local reporting put residential values down about 3.5% on average. Even so, county officials say those averages do not determine any single parcel. For homeowners watching every line on a mortgage statement, the May 1 deadline is the point at which a disputed valuation can still be corrected before it reaches the tax bill.