Lower your Jefferson County property taxes
The Jefferson County Assessor revalues every home in odd-numbered years, and the 2027 values will reflect the market as of June 30, 2026. In 2025, city medians ranged from −7.4% in Mountain View to +6.9% in Golden, so a modest countywide average can hide homes that are valued too high. 30% of first-year savings, only if you save.
What a too-high value costs you
If your home is assessed at $630,000 but similar homes point to about $590,000, you're taxed on $40,000 too much. At a 0.62% rate that's about $248 a year. Our fee would be $74; you'd keep $174.
What gets missed in Jeffco
- The 2027 reappraisal. Every home gets a new value in May 2027, based on sales up to June 30, 2026. Each reappraisal is a fresh chance to protest.
- City-by-city swings. Jeffco's 2025 medians ran from −7.4% to +6.9% by city. A home in a cooling area can be valued like one in a hot one.
- Mountain properties. Foothills homes have few close sales, so the model may lean on homes with different access, views or lot size.
- Condition. An original kitchen, an aging roof or a cracked foundation doesn't show up in the assessor's records.
Insider tip: Jeffco's online comparable sales search shows the same sales the Assessor uses. Pull sales from July 2024 – June 2026 that match your home before you file.
Reviewed by the founder
Julien reviews every Jeffco case personally and tells you the value we’ll ask for before anything is filed.
Get my free reviewJefferson County calendar
| June 30, 2026 | Appraisal date: 2027 values reflect the market on this day |
| By May 1, 2027 | Jefferson County Assessor mails Notices of Valuation (May 1 is a Saturday) |
| May 1 – June 8, 2027 | File your protest with the Jefferson County Assessor |
| By August 15, 2027 | Jefferson County Assessor sends written Notices of Determination |
| September 15, 2027 | Deadline to appeal to the County Board of Equalization |
| By November 1, 2027 | County Board of Equalization decides appeals |
| 30 days after the decision | Appeal to the Board of Assessment Appeals, binding arbitration or district court |
| January 2028 | Tax bills for 2027 mailed |
*Jefferson County Assessor, May 2025: median single-family values rose 2%, to $632,958; 64% of homes changed by less than 5%.
Sources: Jefferson County — 2025/2026 valuation and appeals · Jefferson County — key dates (PDF) · Jefferson County — how taxes are calculated. Dates are checked each year; confirm with the county for your property.
Exemptions to check
If you're 65 or older and have owned and lived in your home for at least 10 years, the senior exemption takes 50% off the first $200,000 of actual value. Qualifying disabled veterans get the same exemption. New senior applications are due by July 15. For 2026, the local-government part of your tax is figured on your value minus 10% of the first $700,000. We check your exemptions free at sign-up.
Jeffco questions
How do I appeal in Jeffco?
Use Online Residential Appeals on the Assessor's website, or mail back the appeal form on your Notice of Valuation, between May 1 and June 8.
When will I hear back?
In 2025 Jeffco used the later reappraisal-year schedule: Notices of Determination by August 15 and County Board of Equalization appeals by September 15. The same applies in 2027.
I missed the deadline. Now what?
Sign up anyway. We'll track your value and file in the next window, which opens May 1, 2027.