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Updated 2025 Tax Year

Washington County
Property Tax Guide

Everything you need to know about property taxes in Washington County, CO. Rates, due dates, exemptions, and how it affects your monthly payment.

10 Official Sources
8 min read
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Quick Facts
Tax Rate
18.85% of assessed value (varies by taxing district)
Exemptions
3+ Available
Section 1

How Property Tax Works

Washington County, Colorado operates on a property tax system that serves as the primary funding mechanism for essential local services including schools, roads, emergency services, and county operations. Property taxes in Washington County are calculated based on the assessed value of real property, which is determined by the county assessor and reassessed every two years. The effective tax rate for residential properties in Washington County for the 2025 tax year is approximately 18.85% of assessed value, though this rate varies significantly based on your property's location within specific taxing districts.

It's important to understand that Washington County contains multiple special taxing districts, including school districts, fire protection districts, library districts, and other special service areas. Each district levies its own taxes, which means your total property tax bill will depend on which combination of districts serve your property. Properties in different areas of the county may experience substantially different tax rates based on their district assignments. The county uses a market-based assessment system where residential properties are assessed at 6.7% of their actual market value for the 2025 tax year.

Section 2

What Makes Up Your Tax Bill

ComponentRateDescription
Base County LevyVariableGeneral county operations, roads, administration
School DistrictVariableK-12 education funding, varies by district
Fire ProtectionVariableEmergency and fire services, district-specific
Library DistrictVariablePublic library services where applicable
Other Special DistrictsVariableWater, sanitation, parks, or other local services
Total Combined Rate (2025)18.8515%Applied to assessed value (residential properties)

Note: These rates apply to the 2025 tax levy year and are applied to the assessed value, not market value. Nonresidential properties face higher assessment rates and correspondingly higher tax bills. Your specific tax rate depends entirely on which special taxing districts serve your property location. Contact the Washington County Assessor's office at (970) 345-2756 to determine which districts apply to your specific property.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Washington County, property taxes are due in two installments:

Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Supplemental taxes in Washington County are additional property tax assessments that occur when there are significant changes to a property outside the regular assessment cycle. The most common triggers for supplemental taxes include new construction, major improvements or additions to existing structures, subdivision of land, or changes in property ownership that reveal previously unreported improvements. These taxes are calculated based on the increased assessed value and are prorated for the remaining portion of the current tax year.

For example, if you complete a $100,000 home addition in June, the county assessor will evaluate the improvement and add the assessed value (6.7% of $100,000 = $6,700) to your property's assessment. You would then owe supplemental taxes on this $6,700 in additional assessed value, multiplied by your local tax rate, prorated from the completion date through the end of the tax year. If your total tax rate is 18.85%, you would owe approximately $1,263 in supplemental taxes ($6,700 × 18.85%), prorated for the months remaining in the tax year.

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (6.7%): $20,100
  • Less Senior Exemption (if qualified): -$0 (requires separate application)
  • Net Taxable Assessed Value: $20,100
  • Annual Tax (18.85%): $3,789
  • Monthly Escrow Amount: $316

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (6.7%): $40,200
  • Less Veteran Exemption (if qualified): -$0 (100% disabled veterans only, requires application)
  • Net Taxable Assessed Value: $40,200
  • Annual Tax (18.85%): $7,578
  • Monthly Escrow Amount: $631

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (6.7%): $67,000
  • Less Available Credits: -$0 (most properties don't qualify for credits)
  • Net Taxable Assessed Value: $67,000
  • Annual Tax (18.85%): $12,630
  • Monthly Escrow Amount: $1,053

Note: Tax credits for seniors and disabled veterans require annual application and have specific qualification requirements. Most properties will not qualify for any credits or exemptions.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Washington County require borrowers to maintain an escrow account for property tax payments, especially for loans with less than 20% down payment. Your lender will estimate your annual property tax liability and collect 1/12th of that amount with each monthly mortgage payment. Since Washington County property taxes are due annually by November 15th, your lender will accumulate these monthly payments throughout the year and make the full payment on your behalf when taxes become due.

Lenders typically conduct an annual escrow analysis to ensure adequate funds are being collected. If property taxes increase due to reassessment or changing tax rates, your lender may adjust your monthly escrow payment and potentially require additional funds to cover any shortfall. Property owners should review their annual escrow statements carefully and understand that tax increases can affect their monthly mortgage payments. If you pay taxes directly without escrow, remember that the full annual amount is due by November 15th, and you're responsible for budgeting this significant expense.

How HonestCasa Helps
  • Understand whether your escrow is set correctly
  • See how rising taxes will change your monthly payment
  • Plan ahead instead of being surprised by "shortage" letters
Section 6

Frequently Asked Questions

Q: When are property taxes due in Washington County for 2025? A: Property taxes are due annually by November 15th. Tax statements are mailed by October 25th, and payments must be postmarked by November 15th to avoid penalties.

Q: What tax credits are available and how do I apply? A: Washington County offers property tax exemptions (which function as credits) for senior citizens, surviving spouses of seniors, and 100% disabled veterans. These require annual application between February 1st and March 2nd. Contact the county assessor at (970) 345-2756 for application forms and qualification requirements.

Q: Is there a homestead exemption that caps my assessment increases? A: Colorado does not have a traditional homestead exemption that caps assessment growth. However, seniors and disabled veterans may qualify for exemption programs that require annual application and have specific income and residency requirements.

Q: How often are properties reassessed? A: Washington County conducts property reassessments every two years as required by Colorado state law. The most recent reassessment affects 2025 taxes, with the next reassessment scheduled for 2027.

Q: What happens if I pay my taxes late? A: Late payments incur penalties and interest charges. Contact the Washington County Treasurer's office at (970) 345-2756 for current penalty rates and payment options if you've missed the November 15th deadline.

Q: Can I pay my property taxes online? A: Yes, Washington County offers online payment options. Visit the county treasurer's website or contact their office for available electronic payment methods and any associated processing fees.

Q: How do special district taxes work? A: Your property may be located within multiple special taxing districts (fire, school, library, etc.). Each district sets its own tax rate, and your total bill reflects the combined rates of all districts serving your property location.

Q: How do I appeal my property assessment? A: If you believe your property is overvalued, you can appeal to the Washington County Board of Equalization. Appeals must typically be filed by June 1st following the assessment year. Contact the county assessor's office for specific procedures and deadlines.

Verified Sources

Backed by 10 Official Government Sources

Every fact in this guide is sourced from official county, state, and federal documents.

01
How is my property value determined?washingtoncounty.colorado.gov
02
County
Washington County Public Access > Property Detailwashcotax.co.washington.or.us
03
County
Washington County Public Access > Property Detailwashcotax.co.washington.or.us
04
County
Washington County Public Access > Homewashcotax.co.washington.or.us
05
General Information and Frequently Asked Questionswashingtoncountyor.gov
06
County
County Treasurerwashcowisco.gov
07
Tax Doc
Property Tax Exemption Program* for Seniors and ...washingtoncounty.colorado.gov
08
Tax Doc
Property Tax Exemptionwashingtoncountyor.gov
09
Homestead Exemptionsleg.colorado.gov
10
State
7/1/19 TO 6/30/20 REAL PROPERTY TAX STATEMENTwashcotax.co.washington.or.us
All sources verified as of 2025 Tax Year

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