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Updated 2025 Tax Year

Warren County
Property Tax Guide

Everything you need to know about property taxes in Warren County, IA. 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
26.02-36.52 per $1,000 assessed value (varies by city and school district)
Exemptions
5+ Available
Section 1

How Property Tax Works

Warren County, Iowa operates under a property tax system that funds essential local services including schools, county government, cities, and special districts. Property taxes are the primary revenue source for these local governments, supporting everything from public safety and road maintenance to educational programs and emergency services.

The effective property tax rates in Warren County vary significantly by location due to different combinations of taxing jurisdictions. For the 2025-2026 tax year, total tax rates range from approximately 26.02 per $1,000 of assessed value in some rural areas to over 36.52 per $1,000 in certain city locations like West Des Moines with Norwalk School District. Your specific rate depends on which city, school district, and special taxing districts serve your property location.

Property in Warren County is assessed at 100% of market value for residential property, with no assessment cap limiting annual increases. However, eligible homeowners may qualify for various tax credits that can reduce their final tax bill, though these require separate applications and are not automatically applied.

Section 2

What Makes Up Your Tax Bill

Warren County Tax Rates for FY 2025-2026 (per $1,000 assessed value):

ComponentRate RangeDescription
County General5.84267Basic county services, sheriff, courts, roads
County Management0.39892County administration and operations
County Debt Service0.78046County bond payments and debt obligations
School Districts15.86344-17.61801Varies by district (Martensdale-St. Marys vs Norwalk)
City Levies0-10.80000Municipal services (varies by city, highest in West Des Moines)
Special Districts0.13415-1.08415Fire districts, drainage districts, other special services
Total Rate26.02339-36.52421Combined rate depends on your specific location

Note: These rates apply to property assessed January 1, 2024, with taxes collected July 1, 2025 through June 30, 2026. Agricultural property receives reduced rates in the same taxing districts.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Warren 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 Warren County are additional tax bills issued when property ownership changes or new construction is completed during the tax year. These taxes cover the period from when the change occurred until the end of the current fiscal year (June 30).

Supplemental taxes are calculated by determining the difference between the old assessed value and new assessed value, then applying the current tax rate to that difference. The amount is prorated based on the number of months remaining in the fiscal year. For example, if you purchase a home in January that was previously assessed at a lower value, you'll receive a supplemental bill for the assessment increase covering January through June.

New construction supplemental taxes are issued once the Warren County Assessor determines the completed value of additions, new buildings, or major improvements. Property owners typically receive supplemental tax bills within 30-60 days of the triggering event, with payment due within 30 days of the bill date.

Example Calculation

Example 1: $300,000 Home in Rural Warren County (Martensdale-St. Marys School District)

  • Market/Assessed Value: $300,000
  • Homestead Tax Credit Applied: -$2,268 (estimated, requires application)
  • Net Taxable Value: $297,732
  • Tax Rate: 26.02339 per $1,000
  • Annual Tax: $7,748
  • Monthly Escrow: $646

Example 2: $600,000 Home in West Des Moines (Norwalk School District)

  • Market/Assessed Value: $600,000
  • Homestead Tax Credit Applied: -$2,268 (estimated, requires application)
  • Net Taxable Value: $597,732
  • Tax Rate: 36.52421 per $1,000
  • Annual Tax: $21,831
  • Monthly Escrow: $1,819

Example 3: $1,000,000 Home in West Des Moines (Norwalk School District)

  • Market/Assessed Value: $1,000,000
  • Homestead Tax Credit Applied: -$2,268 (estimated, requires application)
  • Net Taxable Value: $997,732
  • Tax Rate: 36.52421 per $1,000
  • Annual Tax: $36,438
  • Monthly Escrow: $3,037

Note: Tax credits shown require separate applications and are not automatic. Actual credit amounts may vary based on income and other factors.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Warren County require borrowers to maintain an escrow account for property tax payments. Your lender collects monthly escrow payments along with your mortgage payment, then pays your property taxes directly to Warren County when due.

Warren County property taxes are paid in two installments: the first half is due September 30th, and the second half is due March 31st of the following year. Lenders typically pay both installments on time to avoid penalties. Your lender will provide an annual escrow analysis showing how your monthly escrow payment is calculated based on the previous year's tax bill.

If your property taxes increase due to reassessment or rate changes, your lender may require an escrow shortage payment or increase your monthly escrow amount. You can verify that your lender has paid your taxes correctly by checking with the Warren County Treasurer's office or viewing your account online. Property owners remain ultimately responsible for ensuring taxes are paid even when using escrow services.

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 Warren County property taxes due for FY 2025-2026? A: The first half is due September 30, 2025, and the second half is due March 31, 2026. Delinquent notices are mailed November 1st and May 1st respectively.

Q: What tax credits are available and do I need to apply? A: The Homestead Tax Credit is the main credit for owner-occupied homes, but you must apply with the Warren County Assessor. Military exemptions and disabled veteran credits are also available but require separate applications. None are automatic.

Q: How does the Homestead Tax Credit work? A: The Homestead Credit provides tax relief for owner-occupied properties but requires annual application. You must be an Iowa resident occupying the property on July 1st and for at least six months of the year to qualify.

Q: What's the difference between tax credits and exemptions? A: Tax credits reduce your final tax bill dollar-for-dollar, while exemptions reduce the assessed value subject to tax. Both typically require applications and are not automatically applied.

Q: How often is property reassessed in Warren County? A: Iowa law requires assessment at market value, with the Warren County Assessor reviewing property values regularly. You can appeal your assessment through the Board of Review process if you believe it's incorrect.

Q: What are the penalties for late payment? A: Warren County charges interest and penalties on delinquent property taxes. Contact the Warren County Treasurer's office for current penalty rates and payment options.

Q: Can I pay my property taxes online? A: Yes, Warren County offers online payment options through the Treasurer's website. You can also pay by mail, phone, or in person at the courthouse.

Q: Why do tax rates vary within Warren County? A: Different combinations of school districts, cities, and special taxing districts create varying total tax rates. Rural properties typically have lower rates than those in cities with full municipal services.

Q: What if I disagree with my property assessment? A: You can appeal your assessment to the Warren County Board of Review, typically during April and May. Contact the Warren County Assessor's office for specific deadlines and procedures.

Q: Are there special tax rates for agricultural property? A: Yes, agricultural property receives preferential tax rates in the same taxing districts, with significantly lower effective rates than residential property.

Verified Sources

Backed by 10 Official Government Sources

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

01
2024 Levy Rates Payable FY 25-26.xlsxwarrencountyia.gov
02
2023 Levy Rates Payable FY 24-25warrencountyia.gov
03
Tax Doc
PROPOSED PROPERTY TAX LEVY Fiscal Year July 1, 2025warrencountyia.gov
04
Tax Doc
Property Tax Paymentswarrencountyia.gov
05
Treasurerwarrencountyia.gov
06
Tax Doc
How Do I Pay Property Taxes?iowa.gov
07
Credits & Exemptionswarrencountyia.gov
08
County
Assessor - Warren County, Iowawarrencountyia.gov
09
File a Homestead Exemptioniowa.gov
10
Tax Doc
Property Tax Reformlegis.iowa.gov
All sources verified as of 2025 Tax Year

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