HonestCasa logoHonestCasa
All Tax Guides
Updated 2025 Tax Year

Washington County
Property Tax Guide

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

10 Official Sources
8 min read
Calculate Your True CostMortgage Calculator
Quick Facts
Tax Rate
Varies by taxing district combination - county base rate plus school, fire, library districts as applicable
Exemptions
4+ Available
Section 1

How Property Tax Works

Washington County, Iowa operates under a property tax system that funds essential county services including schools, emergency services, roads, and local government operations. Property taxes are based on assessed values determined by the County Assessor, with tax rates that vary by location within the county depending on which special taxing districts (such as school districts, fire districts, or library districts) serve your specific property.

For the FY 2025-2026 levy year, Washington County has proposed a property tax increase, with the total property tax asking reaching $14,466,437, representing a 2.59% increase from the previous year's $14,101,633. Property owners should expect their actual tax rates to differ based on their specific location within the county, as each combination of overlapping taxing districts creates a unique total rate. The state base rate averages around 1%, but your effective rate will likely be higher when including school districts and other local levies.

Section 2

What Makes Up Your Tax Bill

ComponentRateDescription
County General FundVariesBasic county services, administration, law enforcement
School District LevyVaries by DistrictLocal school funding, varies significantly by school district
Agricultural ExtensionVariesCounty agricultural extension services
Emergency ServicesVariesFire protection, ambulance services by district
Library DistrictVariesPublic library services where applicable
Special AssessmentsVariesDrainage districts, rural improvement districts

Note: Specific rates for FY 2025-2026 are pending final approval following public hearings. Final rates will vary significantly by property location within Washington County based on which combination of taxing districts serve your address. Contact the Washington County Assessor's office for your specific district combination and rates.

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 bills issued when there are changes to property ownership, value, or use during the tax year. Common triggers include new construction completion, property improvements, changes in exemption status, or corrections to the original assessment.

When supplemental taxes are issued, they are calculated based on the difference between the old and new assessed values, multiplied by the applicable tax rate, and prorated for the portion of the tax year remaining. For example, if you complete a $50,000 home addition in January that increases your assessed value, you would receive a supplemental tax bill covering the additional tax owed for the remainder of that fiscal year. These supplemental bills have separate due dates from your regular property tax payments and should be paid promptly to avoid penalties.

Example Calculation

Example 1: $300,000 Home

  • Assessed Value: $300,000
  • Less: Homestead Credit (if applied): Varies
  • Net Taxable Value: ~$300,000
  • Estimated Annual Tax (at ~2% effective rate): $6,000
  • Monthly Escrow: $500

Example 2: $600,000 Home

  • Assessed Value: $600,000
  • Less: Homestead Credit (if applied): Varies
  • Net Taxable Value: ~$600,000
  • Estimated Annual Tax (at ~2% effective rate): $12,000
  • Monthly Escrow: $1,000

Example 3: $1,000,000 Home

  • Assessed Value: $1,000,000
  • Less: Homestead Credit (if applied): Varies
  • Net Taxable Value: ~$1,000,000
  • Estimated Annual Tax (at ~2% effective rate): $20,000
  • Monthly Escrow: $1,667

Note: These examples use estimated rates. Actual rates vary by taxing district location. Credits shown require separate applications and are not automatically applied.

See How Taxes Affect Your Payment

Property taxes are just part of your total monthly cost. Get the full picture.

Calculate Now
Section 5

Escrow & Property Taxes

Most mortgage lenders in Washington County require property tax escrow accounts, where you pay 1/12 of your annual property tax with each monthly mortgage payment. Your lender collects these funds and pays your property taxes directly to Washington County when they become due in September and March.

Property tax statements are mailed between October 17-21 each year. If your property taxes are escrowed, this statement will be sent to your mortgage servicer, though you should also receive a copy. Your lender is responsible for ensuring payments are made by the September 1 and March 1 due dates. You can verify that payments were received by checking with the Washington County Treasurer's office or through their online payment portal. If you believe your escrow account is insufficient or excessive, contact your lender for an escrow analysis and potential adjustment to your monthly payment.

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? A: Property taxes are due twice yearly - the first half by September 1 and the second half by March 1. Late payments incur penalties and interest charges.

Q: What homestead tax credit is available and how do I apply? A: Iowa offers a homestead tax credit that caps assessment increases for qualifying owner-occupied properties. To qualify, you must occupy the home at least six months per year and reside there on July 1. This credit requires a separate application - it is not automatic.

Q: Are there tax credits for senior citizens or disabled persons? A: Yes, Iowa offers various tax credits including elderly/disabled tax credits and military exemptions. Each requires a separate application with specific eligibility requirements and deadlines. Contact the Washington County Assessor's office for current programs and application forms.

Q: How often are properties reassessed in Washington County? A: Iowa requires property reassessments, but frequency varies. Contact the Washington County Assessor's office for the current reassessment schedule and procedures.

Q: How do I appeal my property assessment? A: Assessment appeals must be filed with the Washington County Board of Review. There are specific deadlines and procedures that must be followed. Contact the Assessor's office immediately if you believe your assessment is incorrect.

Q: Can I pay my property taxes online? A: Yes, Washington County typically offers online payment options through their official website. Contact the County Treasurer's office for current online payment procedures and any associated fees.

Q: What happens if I pay my property taxes late? A: Late payments incur penalties and interest charges. Continued non-payment can eventually lead to tax sale proceedings. Pay immediately and contact the Treasurer's office if you're experiencing financial hardship.

Q: Why did my property taxes increase if I didn't improve my property? A: Property tax increases can result from higher tax rates approved by taxing districts, county-wide reassessments, changes in special district boundaries, or loss of previously applied credits that require annual renewal.

Q: What's the difference between timber land and agricultural land tax treatment? A: Timber land of at least 5 acres may qualify for special assessment treatment with specific requirements including livestock exclusion and minimum tree density. This requires separate application and ongoing compliance with state requirements.

Verified Sources

Backed by 10 Official Government Sources

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

01
10000washingtoncounty.iowa.gov
02
Tax Doc
PROPOSED PROPERTY TAX LEVY Fiscal Year July 1, 2025washingtoncounty.iowa.gov
03
State
2025-26 Property Tax Statementwashingtoncountyor.gov
04
County
Frequently Asked Questions - Iowa County Governmentiowacounty.iowa.gov
05
Tax Doc
How Do I Pay Property Taxes?iowa.gov
06
County
Services | Washington County, IA - Official Websitewashingtoncounty.iowa.gov
07
County
Frequently Asked Questions - Worth County, Iowaworthcountyiowa.gov
08
File a Homestead Exemptioniowa.gov
09
County
PROCEEDINGS OF THE WASHINGTON COUNTY BOARD ...washingtoncounty.iowa.gov
10
Other individuals in attendance included ...washingtoncounty.iowa.gov
All sources verified as of 2025 Tax Year

See the Full Picture of Your Home Costs

Property taxes are just one piece of homeownership. HonestCasa helps you understand your total monthly cost and explore safe ways to access your home equity.

Total Monthly Cost

Mortgage + taxes + insurance + HOA

Equity Growth

Track how your equity grows over time

Safe Equity Access

Options for projects or debt payoff

Run Your ScenarioTry Calculator

Free • No credit check • 2-minute estimate