Updated assessment rates for 2025 taxes (payable in 2026) and new “split” residential assessed values in your tax bill

• Last year’s tax break ended: The $55,000 value reduction that helped lower taxes in 2024 is not available for 2025. Some people may have higher tax bills, even if their home value didn’t change much.
• Two assessment rates for homes: For the 2025 tax year (paid in 2026), homes use two different rates. You may see two “assessed values” on your notice—one for schools and one for other local services (like the county, city, fire district, etc.).
• How you can pay: The Treasurer’s office still offers two ways to pay:
  --Pay all at once, or
  --Pay in two payments (installments).
• Need help or have questions?
  --Look closely at your tax bill.
  --Call the Assessor for value questions or appeals (303-441-3530).
  --Call the Treasurer for tax bill and payment questions (303-441-3520).

Boulder County, Colo. — When Boulder County property owners receive their 2025 property tax bills (payable in 2026), they may notice some important changes: the value reduction of $55,000 has been eliminated this year, and residential properties now use two assessment rates.

What’s changing for 2025 taxes (payable in 2026)

In recent years, the state provided temporary relief measures—including a $55,000 reduction in residential value—that helped lower many tax bills. Those temporary reductions expired for 2025. As a result, some property owners may see higher bills than in 2024, even if their property values did not change much.

Manufactured home owners may see a big increase in their tax bills for 2025 due to the loss of the value reduction. For example, a home valued at $100,000 would have a tax bill of around $275 in 2024 and could have a tax bill of around $550 in 2025.

In addition, residential properties now use two assessment rates (and two assessed values)

For tax year 2025 (paid in 2026), Boulder County residential property is assessed at:

• 7.05% for school districts
• 6.25% for all other local governments

Because of this, your tax calculation is now essentially shown in two parts:

• Schools assessed value → schools’ taxes
• Other local assessed value → other local taxes

Seeing two assessed values on your notice is expected for residential property in 2025; it’s not an error.

Residents should keep in mind the payment options for 2026 payments:

• Two installments: March 2, 2026, and June 15, 2026
• Full payment: April 30, 2026

For many nonresidential property types in 2025 (paid in 2026), Boulder County lists a 27% assessment rate, including commercial, vacant land, agricultural, and renewable energy property types. State law describes this as a reduction from the long-standing 29% non-residential valuation for certain categories.

“Property taxes can feel complicated. Our goal is to make this as clear and stress-free as possible,” said Assessor Cynthia Braddock. “If you have questions about your value notice, the new split residential rates, or want guidance in how to appeal your tax bill, please reach out. We are here to help you understand your information and your options.”

Tax Deferral for Seniors and Active-Duty Military

Starting with taxes due in 2026 and later, the Boulder County Treasurer’s Office will again take tax deferral applications.

A 2025 law (SB25-261) changed how the program works; County Treasurer’s offices handle the application process, while the Colorado State Treasurer’s Office still manages the deferral loans (the money that covers the taxes). You can apply by phone (303-441-3520) or by emailing treasurer@bouldercounty.gov. We accept applications from January through mid-March for taxes due that year.

How your property taxes are calculated

Your tax bill is based on three key pieces:

Actual value (the Assessor’s estimate of market value)

Assessment rate (set in state law)

Mill levy (tax rates set by local taxing authorities like school districts, cities, fire districts, and others)

For 2025 residential property, the calculation is shown separately for schools and other local governments, then added together for your total.

Looking ahead to 2026 (future changes in state law)

State law also includes additional changes scheduled for the 2026 tax year, including:

• A home value deduction (10% up to a cap described in law) when calculating some residential taxes, and
• A decrease in the commercial and agricultural valuation for assessment to 25% starting in 2026.

As always, future legislation can change, but these are the changes currently described in state law.

Need help?

For questions about your property’s value or classification, contact the Assessor’s Office at 303-441-3530 or email assessor@bouldercounty.gov.

You can also contact the Treasurer’s Office for questions about paying your bill, due dates, or payment status. Staff can be reached at 303-441-3520 or by emailing treasurer@bouldercounty.gov.

Property owners can also use the Treasurer’s online property tax portal to look up and pay taxes.