Property tax in Summit County, Colorado is calculated by multiplying your property’s actual value by the state assessment rate for its class, then by the combined mill levy of every taxing district that covers your parcel. For the 2026 tax year, residential property is assessed at 6.8% for local government levies and 7.05% for the school district levy, while most commercial and vacant land sits at 25% to 26%. You can pay the full bill by April 30 or split it into two installments due the last day of February and June 15.
How Your Bill Is Calculated
Three numbers determine what you owe. The assessor sets your property’s actual value, which is essentially fair market value. That figure is multiplied by the assessment rate for your property’s classification to produce the assessed value. The assessed value is then multiplied by the total mill levy for your tax area.
A mill equals one dollar of tax per $1,000 of assessed value.1Assessors’ Library. Chapter 4 – Assessment Math So if your home carries an assessed value of $40,000 and the combined mill levy where you live is 50 mills, the annual bill is $2,000. The arithmetic is straightforward. The rules behind each input are where things get specific.
2026 Assessment Rates
Residential property has two separate assessment rates for 2026: 6.8% for every non-school levy and 7.05% for the school district levy.2Colorado Department of Local Affairs Division of Property Taxation. Residential Local Government Assessment Rate Your bill is calculated twice using those rates and then added together.3Colorado Department of Local Affairs Division of Property Taxation. Understanding Property Taxes in Colorado The local government rate also includes a 10% reduction applied to the first $700,000 of actual value, with a minimum assessed value of $1,000.
Nonresidential rates for the 2026 tax year:
- Commercial improved property: 25% of actual value
- Vacant land and other commercial property: 26% of actual value
- Agricultural property: 25% of actual value
These come from a phased schedule in state law, and most nonresidential property drops to a uniform 25% in 2027.4Justia. Colorado Code Title 39 – Section 39-1-104
Why Values Usually Stay the Same in 2026
Colorado runs on a two-year assessment cycle. Odd years are reappraisal years; even years are intervening years when values generally carry over.5Summit County, CO. Homeowners For 2026, your actual value most likely reflects what the assessor set in the 2025 reappraisal.
That 2025 figure answers a specific question: what was the property worth on June 30, 2024, based on its condition as of January 1, 2025?6Summit Daily News. Summit County Property Owners to Receive Notices of Valuation From Local Assessors Office This Year The assessor draws on sales from at least the 18 months before that date, extendable up to 60 months if activity is thin.7Summit County Assessor. 2025 Reappraisal Facts Sales after June 30, 2024 don’t factor in until the 2027 reappraisal.
Mill Levies Depend on Where You Live
Summit County contains many tax areas, each with its own combined mill levy reflecting the county, town, fire district, water district, community college district, and school district that serve a given parcel.8Summit County, CO. Understanding Property Taxes in Colorado 2025-2027 Two homes of identical value sitting in different parts of the county can produce meaningfully different tax bills. The exact mill levy for your parcel appears on your annual tax statement and is available from the Summit County Treasurer’s office.
Payment Deadlines and Methods
You have two ways to pay. The full amount is due by April 30, or you can split the bill into two equal installments: the first due the last day of February, the second by June 15.9Justia. Colorado Code Title 39 – Section 39-10-104.5 If the total bill is under $25, the installment option isn’t available and you have to pay in full.
Summit County accepts payments online, in person at the Treasurer’s office, or by mail. Online payments go through credit card (Visa, Mastercard, American Express, Discover) or directly from a checking or savings account. A third-party convenience fee applies: $1.00 for electronic check, or 2.25% plus $0.75 per transaction for credit cards.10Summit County, CO. Property Taxes On a $5,000 bill, the credit card fee runs over $110, so the electronic check option saves real money.
If you have an escrow account with your mortgage, your lender typically pays the tax directly. Check with the servicer before paying yourself.
What Happens If You Pay Late
Missed deadlines trigger delinquent interest at 1% per month.9Justia. Colorado Code Title 39 – Section 39-10-104.5 Miss the February installment and interest runs from March 1. Miss June 15 and interest on that half starts June 16. Miss the April 30 full-payment deadline and interest runs on the entire balance from May 1. One safety valve: if your tax statement arrives late, you get a 30-day grace period after mailing before interest hits the first installment.
Taxes still unpaid after the deadlines are eventually sold at the county’s annual tax lien sale, held in the fall. Investors pay the delinquent taxes and receive a tax lien certificate that earns interest at a rate set each September by the state banking commissioner, calculated as nine percentage points above the Federal Reserve Bank of Kansas City’s discount rate. For Summit County’s 2024 sale, that rate was 14%.11Summit County, CO. Tax Liens/Tax Lien Sale
You can redeem the lien at any time by paying the sale amount plus accrued investor interest in certified funds. If the lien stays unredeemed for three years, the certificate holder can apply for a Treasurer’s Deed and take ownership. That process requires a $1,000 deposit and takes roughly six months.11Summit County, CO. Tax Liens/Tax Lien Sale Losing a property this way is uncommon, but the compounding interest makes delinquency expensive long before it gets there.
Protesting Your Valuation
If you think the assessor overvalued your property in a reappraisal year, you can protest. Notices of Valuation go out around May 1 showing current and previous actual values.6Summit Daily News. Summit County Property Owners to Receive Notices of Valuation From Local Assessors Office This Year In Summit County, the real property protest deadline is June 8, and the personal property deadline is June 30. Late filings aren’t accepted. If the deadline falls on a weekend or holiday, the next business day applies.12Summit County, Colorado. Summit County Assessor – Appeals
The strongest protests rest on comparable sales from the assessor’s data collection period. For the 2025 reappraisal that means sales on or before June 30, 2024. Comparables should match on size, age, condition, and location. Physical defects or negative influences like road noise are worth documenting too.
Protests can be filed through the county’s online portal, by mail postmarked by the deadline, or by hand delivery to the assessor’s office. The assessor issues a Notice of Determination by the last working day of June for real property. A denial has to include written reasons under state law.13Justia. Colorado Code Title 39 – Section 39-5-122 A bare denial without reasoning doesn’t satisfy that requirement.
Appeals Beyond the Assessor
A denial isn’t the end. You can appeal to the County Board of Equalization (CBOE) by filing a letter or appearing in person no later than July 20. If July 20 is a weekend or holiday, the next business day applies.14Colorado Department of Local Affairs Division of Property Taxation. Protests and Appeals
If the CBOE rules against you, three further paths exist: the state Board of Assessment Appeals (BAA), district court, or binding arbitration.14Colorado Department of Local Affairs Division of Property Taxation. Protests and Appeals The BAA is the more common choice for homeowners because it’s less formal than court. Representing yourself, the first two BAA filings per fiscal year are free. After that, or if you use an attorney or agent, the fee is $101.25 per parcel.15Board of Assessment Appeals. Filing Fees
Exemptions and Tax Relief
Colorado’s senior and disabled veteran exemption removes 50% of the first $200,000 of actual value from taxation.16Colorado Department of Local Affairs Division of Property Taxation. Senior Citizen and Veterans With a Disability Property Tax Exemption and Senior Primary Residence Classification On a $500,000 home, that pulls $100,000 off the taxable base, worth roughly $340 or more depending on your mill levy.
Eligibility splits by category. Seniors applying for the 2026 tax year must have been born on or before January 1, 1961, and must have owned and occupied the home as a primary residence continuously since January 1, 2016. Disabled veterans need a VA-approved disability rating; there is no age or ten-year ownership requirement, but you must own and occupy the home as a primary residence as of January 1, 2026.16Colorado Department of Local Affairs Division of Property Taxation. Senior Citizen and Veterans With a Disability Property Tax Exemption and Senior Primary Residence Classification
Senior Primary Residence Classification
If you qualified for the senior exemption at a former home in 2020 or later but moved and no longer meet the ten-year rule, the Senior Primary Residence Classification may apply instead. It’s available for the 2025 and 2026 tax years and provides a reduced assessment rate rather than a dollar exemption. A surviving spouse who hasn’t remarried may also qualify.17Colorado Department of Local Affairs Division of Property Taxation. Senior Primary Residence Classification
Property Tax Deferral
The state’s Property Tax Deferral Program lets qualifying homeowners postpone their taxes through a low-interest loan secured against the home. It’s open to homeowners 65 and older and to active-duty military personnel.18Colorado Property Tax Deferral Program. Colorado Property Tax Deferral Program Applications are filed between January 1 and April 1 each year. You must have no delinquent taxes, and total liens against the property (including the deferral) can’t exceed thresholds tied to assessed value. The deferred amount is repaid when the property sells or the owner passes away.