Colorado Property Tax 2026: 6.7% Assessment Ratio, Senior Homestead and Post-Gallagher

Colorado's property tax system has been through three major upheavals since 2020: the Gallagher Amendment was repealed, Proposition HH was defeated at the ballot, and the legislature reduced the residential assessment rate from 6.765% to 6.7% in a 2023 special session. This 2026 guide explains the current landscape — how the rate works, the senior homestead exemption, the 10% first-$700,000 actual value reduction, and the 45-day window to appeal to the county Board of Equalization.

How Colorado Property Tax Works

Colorado property tax is administered by 64 county assessors under oversight from the Colorado Department of Local Affairs, Division of Property Taxation. Tax rates (mill levies) are set annually by each taxing jurisdiction: counties, municipalities, school districts, special districts, and fire/library/water districts.

The tax calculation

Assessment ratios vary by property type. For tax year 2026:

• Residential: 6.7% (with 10% actual value reduction on first $700,000 — effective rate around 6.4-6.8% depending on value)
• Commercial: 27.9% (reduced from 29%)
• Agricultural: 26.4% of ag use value (low)
• Multifamily rental: 6.8%

Reassessment cycle

Colorado reassesses all property every two years (odd-numbered years). The 2025 reassessment set values for tax years 2025 and 2026. The next reassessment will be in 2027 for tax years 2027 and 2028.

The Gallagher Repeal and Recent Rate Changes

Colorado's property tax was governed from 1982 to 2020 by the Gallagher Amendment, which constitutionally required that residential property carry 45% of the total assessed value statewide — adjusting the residential assessment ratio downward as home values grew faster than commercial. Under Gallagher, the residential rate fell from 21% (1982) to 7.15% (2019).

Gallagher repealed (November 2020)

Amendment B, approved by voters in November 2020, repealed the Gallagher Amendment. This fixed the residential rate at its 2020 level (7.15%) but eliminated the automatic ratcheting mechanism. The legislature now has authority to set assessment rates statutorily.

Proposition HH defeated (November 2023)

Proposition HH would have reduced the residential rate to 6.7% in exchange for reducing TABOR refund amounts. Voters rejected it. However, the legislature convened a special session shortly after and passed similar rate relief without the TABOR offset, reducing the rate to 6.7% and raising the actual-value reduction to $55,000 (later expanded).

Current 2026 rates

• Residential assessment rate: 6.7%
• Actual value reduction: 10% of the first $700,000 of actual value (applies to primary residences)
• Effective rate for a median home: approximately 6.4% to 6.8%

Senior Property Tax Homestead Exemption

Colorado's constitutional senior homestead exemption, authorized by Section 3.5 of Article X, provides:

Benefit

50 percent of the first $200,000 of actual value is exempt from property tax. Equivalent to up to $100,000 of actual value excluded from the tax calculation.

Eligibility for 2026

• Age 65 or older on January 1 of the tax year
• Owned and occupied the property as primary residence for at least 10 consecutive years
• Some limited exceptions for elderly disabled individuals forced to move into qualifying care facilities

Disabled veteran variation

Disabled veterans with 100% service-connected permanent total disability (or surviving spouses) qualify for the same 50%/first-$200,000 exemption without the 10-year residency requirement. File form DR-8700 with the county assessor.

Budget funding constraint

The exemption is funded by the state, not the local taxing authority. In years when the state cannot fund it fully, the benefit may be reduced or temporarily suspended (has happened in past recession years). For 2026, full funding is in place.

Application

File form 15DPT-AR with the county assessor, typically by July 15 of the tax year. Once approved, continues automatically.

Other Exemptions and Programs

Senior Deferral Program

Colorado offers a property tax deferral for qualifying seniors (age 65+ or active military) who meet household income limits. Deferred tax accrues interest at the state-certified rate and is repaid when the property is sold, the owner dies, or the owner no longer qualifies. State Treasurer administers.

Senior Property Tax Work-Off Program

Some Colorado counties offer a senior work-off program where qualifying seniors perform community service or governmental work in exchange for property tax credit. Locally administered; availability varies.

Agricultural Land

Property actively used for agricultural production is assessed at 26.4% of agricultural use value (not market value). For farms in growing areas, this can reduce assessed value by 70-90%.

Disabled Veteran Exemption

50% exemption on first $200,000 of actual value for 100% service-connected permanent total disability veterans. File DR-8700 with county assessor.

Property Tax/Rent/Heat Credit (PTC)

A state income tax credit (not a property tax exemption) up to $876 for 2025 filings, for low-income seniors and disabled residents. Claimed with Colorado Form 104PTC. Income limit approximately $19,700 (single).

Appealing Your Assessment

Colorado assessment appeals start at the county assessor and escalate through county BOE to the Board of Assessment Appeals and Colorado courts.

Step 1: Notice of Valuation (early May)

Assessors mail the Notice of Valuation by May 1 each year in reassessment years (and in non-reassessment years when value changes). Review immediately.

Step 2: Protest to the County Assessor

File a protest with the county assessor by June 1 (in reassessment years) or the deadline stated on the notice. No fee. Assessor must respond by the last working day of June.

Step 3: County Board of Equalization (BOE)

Appeal to the county BOE by July 15 (the deadline varies slightly by county). BOE hearings are informal; no attorney required.

Step 4: Board of Assessment Appeals (state)

From county BOE, appeal to the Colorado Board of Assessment Appeals within 30 days of the BOE decision. Alternatively, appeal directly to District Court or to arbitration.

Evidence that wins

• Recent arm's-length sale below the assessed actual value
• Comparable sales from the 18-month base period before the assessment date (January 1 of the prior year in reassessment years)
• Physical attribute errors on the property record
• Independent appraisal

Payment Schedule

Colorado property tax for a given year is billed and paid the following year. The tax year 2025 bill is paid in 2026.

Payment options

• Full payment: due by April 30 of the payment year
• Two equal installments: first due by February 28, second by June 15

Delinquent tax becomes a tax lien on November 1 and is sold at the county tax lien sale in November. The property owner has a 3-year redemption period to pay delinquent tax plus interest before the tax-lien holder can apply for treasurer's deed.

Frequently Asked Questions

What is Colorado's residential property tax assessment rate in 2026?

6.7% of actual value, further reduced by a 10% reduction on the first $700,000 of actual value for primary residences. Effective rates for typical homes range from about 6.4% to 6.8% depending on value. The rate is set statutorily by the legislature following the 2020 repeal of the Gallagher Amendment.

What is the Colorado Senior Property Tax Homestead Exemption?

50 percent of the first $200,000 of actual value is exempt from property tax for homeowners age 65+ who have owned and occupied the property as primary residence for at least 10 consecutive years. File form 15DPT-AR with the county assessor by July 15. Disabled veterans (100% SC) qualify for the same benefit without the 10-year requirement.

When is the Colorado property tax appeal deadline?

File protest with the county assessor by June 1 (in reassessment years) or the deadline on the Notice of Valuation. If dissatisfied, appeal to the county Board of Equalization by July 15. From there, escalate to the Colorado Board of Assessment Appeals within 30 days of the BOE decision, or to District Court or arbitration.

Does Colorado still have the Gallagher Amendment?

No. Gallagher was repealed by Amendment B in November 2020. Before the repeal, Gallagher required residential property to carry 45% of total assessed value statewide, which caused the residential rate to ratchet downward as home values grew. Post-repeal, rates are set statutorily by the legislature, currently 6.7% residential.

How often does Colorado reassess property?

Every two years, in odd-numbered years. The 2025 reassessment set values for tax years 2025 and 2026. The next reassessment will be in 2027 for tax years 2027 and 2028. Between reassessments, values adjust only for physical changes (new construction, demolition, or major improvements).