Photo: Elmschrat / Wikimedia Commons, CC BY-SA 3.0
Every two years, homeowners in Larimer and Weld counties receive a notice of valuation from the county assessor. The value on it drives the property tax bill that arrives the following January. Here is how the number is set and what to do if you think it is wrong.
The two-year cycle
Colorado reappraises all property in odd-numbered years. The 2025 values, for example, were based on sales and market data from an 18-month period ending June 30, 2024. State law bars assessors from using later data, which will be considered in the 2027 reappraisal. In even years, values usually carry over unless a property changed, for instance through new construction.
What the notice shows
The notice of valuation, mailed by May 1, lists the property’s actual value for the current and previous year and an estimate of taxes. The actual value is not what you pay tax on. An assessment rate set by the state is applied first, and local mill levies are then applied to the result. In recent years the legislature has changed residential assessment rates several times. A change in the rate is not grounds for an appeal; only the value and the classification are.
Step 1: check the facts
Start with the assessor’s online property record. Check square footage, number of bedrooms and bathrooms, basement finish, lot size and the year built. Errors in these details are among the easiest appeals to win.
Step 2: compare sales
Look at sales of similar homes in your neighborhood during the study period. Both assessors publish sales data online. If similar homes sold for less than your valuation, those sales are your strongest evidence. Photos of condition problems, contractor bids for needed repairs and a recent appraisal can also help.
Step 3: file with the assessor
To preserve your right to appeal, you must file an objection with the assessor by June 8 (or the next business day if June 8 falls on a weekend or holiday). You can usually file online, by mail or in person. Larimer and Weld are both large enough that state law requires them to use the alternate protest schedule in reappraisal years, which gives the assessor until August 15 to mail a notice of determination.
Step 4: if you disagree
If you are not satisfied with the assessor’s decision, you can appeal to the County Board of Equalization, generally by September 15 in a reappraisal year. After that, you may appeal to the state Board of Assessment Appeals, to district court or to binding arbitration. If you miss the June deadline, you may still be able to file an abatement petition after taxes are levied.
Across the line in Wyoming
Wyoming values property every year and sends assessment notices each spring. Owners have a short window, generally 30 days, to appeal to the county board of equalization. For a fuller comparison, see our guide to what a household pays in taxes on each side of the state line.
Sources
- Larimer County Assessor and Weld County Assessor, notice of valuation and appeal information.
- Colorado Revised Statutes 39-5-121, 39-5-122 and 39-5-122.7; Colorado Department of Local Affairs, Division of Property Taxation.
- Wyoming Department of Revenue, Property Tax Division.
