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Updated 2025 Tax Year

Mills County
Property Tax Guide

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

10 Official Sources
8 min read
Quick Facts
Tax Rate
1.5% to 2.2% of assessed value, varies by taxing districts (school, city, county)
Exemptions
5+ Available
Section 1

How Property Tax Works

Mills County property taxes fund essential local services including schools, law enforcement, emergency services, road maintenance, and county government operations. The property tax system in Iowa is based on assessed value, with Mills County's effective tax rates typically ranging from 1.5% to 2.2% of assessed value, depending on your specific location within the county.

Your actual property tax rate varies significantly based on the special taxing districts where your property is located, including school districts, city boundaries, and other local improvement districts. The county assessor determines property values, while various local government entities set their individual levy rates that combine to create your total tax bill. Property owners are responsible for applying for available tax credits and exemptions, as most are not automatically applied.

Section 2

What Makes Up Your Tax Bill

Based on available data for Mills County, specific levy rates for FY 2025-2026 are still being finalized by the county board. Property values are expected to reflect approximately a 10% increase for the 2025 assessment year.

ComponentEstimated Rate RangeDescription
County General$3.50-4.50 per $1,000County operations, services
School District$12.00-16.00 per $1,000Local school funding
City/Municipal$8.00-12.00 per $1,000City services (varies by city)
Special Districts$1.00-3.00 per $1,000Fire, ambulance, drainage districts
Total Estimated$24.50-35.50 per $1,000Combined effective rate

Note: Rates vary significantly by location within Mills County based on your specific taxing districts. Final rates for FY 2025-2026 will be determined by each governing body.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Mills 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 Mills County are additional property tax assessments that occur when there are changes to property ownership, new construction, or improvements completed after the annual assessment date. These taxes cover the difference between what was originally assessed and what should have been assessed for the partial tax year.

Supplemental taxes are calculated by determining the difference between the new assessed value and the original assessed value, then applying the current tax rate to that difference, prorated for the portion of the tax year remaining. For example, if you complete a $100,000 home addition in January and the annual assessment was already completed, you would receive a supplemental tax bill for the additional assessed value covering the remaining months of that tax year. The county may also abate portions of supplemental taxes in certain circumstances, as evidenced by Mills County's recent abatement of $126,942.22 for the 2024 assessment.

Example Calculation

Example 1: $300,000 Home

  • Assessed Value: $300,000
  • Homestead Credit Applied: Caps assessment increase at 10%
  • Net Taxable Value: $300,000
  • Tax Rate: $28.50 per $1,000 (estimated)
  • Annual Tax: $8,550
  • Monthly Escrow: $712.50

Example 2: $600,000 Home

  • Assessed Value: $600,000
  • Homestead Credit Applied: Caps assessment increase at 10%
  • Net Taxable Value: $600,000
  • Tax Rate: $30.00 per $1,000 (estimated)
  • Annual Tax: $18,000
  • Monthly Escrow: $1,500

Example 3: $1,000,000 Home

  • Assessed Value: $1,000,000
  • Military Exemption: $1,852 credit (if applicable and filed)
  • Net Tax After Credits: Based on full assessed value minus applicable credits
  • Tax Rate: $32.00 per $1,000 (estimated)
  • Annual Tax: $32,000 - $1,852 = $30,148
  • Monthly Escrow: $2,512

Note: All tax credits require separate applications and are not automatically applied. Homestead credits must be filed by February 1st annually.

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Section 5

Escrow & Property Taxes

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

Lenders typically conduct annual escrow analyses to ensure adequate funds are collected, and may adjust your monthly payment up or down based on actual tax bills and account balances. You should receive an annual escrow statement showing all deposits, payments, and any shortage or surplus. If your property taxes increase significantly due to reassessment or rate changes, your lender may require additional monthly payments or a lump sum to cover any escrow shortage. Property owners remain ultimately responsible for ensuring taxes are paid on time, 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 property taxes due in Mills County for FY 2025-2026? A: Property taxes are due in two installments - the first installment by September 1, 2025, and the second installment by March 1, 2026. Unpaid taxes after April 1 may result in a tax sale.

Q: What tax credits are available and do I need to apply? A: Available tax credits include Homestead Credit, 100% Disabled Veterans Homestead Tax Credit, and Military Exemptions. All credits require separate applications filed with the county assessor by February 1st of each assessment year - none are automatic.

Q: How does the Homestead Credit work? A: The Homestead Credit limits the annual increase in your assessed value to 10% for residential properties. It does not reduce your market value but caps assessment growth. You must apply by February 1st annually - it's not automatically renewed.

Q: How often are properties reassessed in Mills County? A: Iowa law requires properties to be assessed annually. The county assessor reviews property values each year, with physical inspections conducted on a rotating basis or when significant changes occur.

Q: What are the penalties for late payment? A: Late payments after the September 1st and March 1st due dates incur interest and penalties. Properties with unpaid taxes after April 1st may be subject to tax sale proceedings.

Q: Can I pay my property taxes online? A: Contact the Mills County Treasurer's office for current online payment options and accepted payment methods, as these services may vary and update periodically.

Q: Why do tax rates vary within Mills County? A: Your total tax rate depends on all the taxing districts where your property is located, including school district, city boundaries, fire districts, and other special assessment districts, which each set their own levy rates.

Q: How do I appeal my property assessment? A: Property assessment appeals must be filed with the Mills County Board of Review. Contact the county assessor's office for specific deadlines and appeal procedures, typically available in April and May.

Q: Are senior citizens eligible for any special tax relief? A: Iowa offers various programs for seniors including property tax deferrals and credits. Contact the Mills County Assessor's office to learn about eligibility requirements and application procedures.

Q: What happens if I disagree with a supplemental tax assessment? A: You can appeal supplemental tax assessments through the same process as regular assessments. Contact the county assessor's office promptly to understand your appeal rights and deadlines.

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