Why did my property taxes go up?

Why did my property taxes go up?

If you recently received a 2025 property tax notice and felt a little sticker shock, you’re not alone.

Many Boulder County property owners are seeing a higher tax bill for 2025, and there are a few reasons for the change: Updated property valuations, expiration of a temporary tax break, and a change in how your property tax is assessed.

It’s tough to see taxes increase, but understanding the changes can help make the numbers a little less surprising.

Updated property values

The first reason for a higher property tax is likely due to a higher home value. Every odd-numbered year, the Boulder County Assessor’s Office is required to reassess the value of real estate countywide. This reassessment, required by state law, was last done in 2025.

Since Boulder County home values typically rise — good news for homeowners — the new valuation is typically higher, which results in a higher property tax.

To determine the property values for 2025 taxes, the Assessor’s Office analyzed comparable home sales of similar properties and reviewed information from property appeals based on a 24-month period from July 1, 2022, through June 30, 2024.

The new property values were then used by the Boulder County Treasurer’s Office to calculate property taxes due for the 2025 tax year. But that is only the starting point for calculating property tax. Your final tax bill is based on three factors:

1.Actual value determined by the Assessor’s Office.

2.Assessment rate, set in law.

3.Mill levy, set by Boulder County taxing authorities, including school districts, cities, and fire districts.

Why taxes can increase even if your home value didn’t change much

Another factor affecting 2025 property taxes is the expiration of a temporary tax relief measure.

In recent years, the state provided short-term relief by reducing the assessed value of residential property by $55,000. That reduction helped lower taxes in 2024, but it is no longer available for 2025, according to the Boulder County Assessor's Office.

So even if your home’s assessed value stayed relatively flat, you may have a higher tax bill.

Homeowners of manufactured homes are likely to feel the loss of the value reduction most acutely, since it could significantly increase their 2025 tax bill. For example, the 2024 tax bill for a manufactured home valued at $100,000 would be about $275 and could roughly double to $550 without the value reduction.

Why you’ll see two tax categories

Also in 2025, you will see the assessment rate for residential property taxes split into two categories, one calculated for schools and another for local services. These two are then added together for the total. For tax year 2025, Boulder County residential property is assessed:

·7.05% for school districts

·6.25% for all other local governments

The two calculations are shown separately, then added together.

Property tax exemptions for seniors and disabled veterans

Fortunately, there is some relief available for senior citizens and disabled veterans. Beginning in 2002 and 2007, respectively, qualifying senior citizens and disabled veterans were eligible for the Senior Homestead Property Tax Exemption of 50% on the first $200,000 of the residential property value. The property must be owner-occupied and have been the owner's primary residence for the past 10 years.

For taxes due in 2026 and later, the Boulder County Treasurer’s Office will again accept applications for this property tax deferral program. But due to a new 2025 law there has been a change in how the program is administered. The County Treasurer’s office now handles applications, while the Colorado State Treasurer’s Office manages the deferral loans that cover the taxes.

To qualify for senior exemption for the 2026 tax year, payable in 2027, applicants must have been born on or before Jan. 1, 1961, and owned and lived in the home as their primary residence continuously starting before Jan. 1, 2016.

You can learn more and apply for the exemption on the BoulderCounty.gov website.

Bottom line

If your property tax bill looks different this year, it’s likely due to these multiple changes. To look up your property’s current valuation and assessed taxes, go to the Boulder County property tax portal (https://treasurer.bouldercounty.org/treasurer/web/).