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Updated 2025 Tax Year

Mahaska County
Property Tax Guide

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

10 Official Sources
8 min read
Quick Facts
Tax Rate
Varies by location, typically 1.5-2.5% effective rate depending on school district and municipal levies
1st Due
Sep 30
2nd Due
Mar 31
Exemptions
5+ Available
Section 1

How Property Tax Works

Mahaska County, founded in 1851 and named after Chief Mahaska of the Iowa tribe, operates on Iowa's property tax system where taxes are levied to fund essential county services including schools, roads, public safety, and local government operations. Property taxes are calculated based on assessed value multiplied by the total tax rate, which includes levies from the county, cities, school districts, and various special taxing districts within your area.

The effective property tax rate in Mahaska County varies significantly depending on your specific location within the county, as different areas are served by different school districts, cities, and special taxing districts such as fire departments, library districts, and emergency services. While Iowa's statewide average is approximately 1%, your actual rate in Mahaska County will depend on the combination of taxing authorities that serve your property. The county is currently in the process of setting tax rates for FY 2026, with a public hearing scheduled for March 31, 2025, at 6:30 PM to finalize the proposed property tax levy.

Section 2

What Makes Up Your Tax Bill

ComponentRateDescription
County General FundTBDBasic county operations, roads, public safety
School District LevyVariesLocal school district operations and bonds
City/Municipal LevyVariesCity services (police, fire, utilities, parks)
Township LevyVariesRural fire protection and road maintenance
General Supplemental~$0.15 per $1,000Additional county operational funding
Records Management Fund~$0.12 per $1,000Court and county records management
Special DistrictsVariesLibrary, emergency services, drainage districts

Rates shown are estimates based on FY 2025 data. Final rates for FY 2026 (tax year 2025) will be determined at the public hearing on March 31, 2025. Your total rate depends on which taxing districts serve your specific property location within Mahaska County.

Section 3

When Are Property Taxes Due?

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

First Installment
Sep 30
Delinquent after Dec 10
Second Installment
Mar 31
Delinquent after Apr 10
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 Mahaska County are additional assessments that may be levied mid-year when significant changes occur to your property. The most common triggers include new construction completion, major improvements or additions, ownership transfers that reveal unreported improvements, or corrections to assessment errors discovered after the initial tax bill was issued.

Supplemental taxes are calculated using the same tax rate as your regular property tax, applied to the difference between your original assessed value and the new assessed value. For example, if you completed a $50,000 home addition and your total tax rate is 3.5%, your supplemental tax would be approximately $1,750 ($50,000 × 0.035). The county maintains separate funds for general supplemental taxes, which have historically generated around $22,000-$24,000 annually for county operations.

Example Calculation

Example 1: $300,000 Home (with Homestead Credit)

  • Assessed Value: $300,000
  • Homestead Credit Applied: -$4,850 (estimated rollback)
  • Net Taxable Value: $295,150
  • Estimated Tax Rate: 3.2%
  • Annual Tax: $9,445
  • Monthly Escrow: $787

Example 2: $600,000 Home (with Homestead Credit)

  • Assessed Value: $600,000
  • Homestead Credit Applied: -$4,850 (estimated rollback)
  • Net Taxable Value: $595,150
  • Estimated Tax Rate: 3.4%
  • Annual Tax: $20,235
  • Monthly Escrow: $1,686

Example 3: $1,000,000 Home (no credits)

  • Assessed Value: $1,000,000
  • Credits Applied: $0 (assuming no application filed)
  • Net Taxable Value: $1,000,000
  • Estimated Tax Rate: 3.5%
  • Annual Tax: $35,000
  • Monthly Escrow: $2,917

Note: Homestead and other tax credits require annual application by July 1st deadline. Tax rates vary by location within the county based on special taxing districts.

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Section 5

Escrow & Property Taxes

If you have a mortgage, your lender typically collects property taxes through your monthly mortgage payment and holds these funds in an escrow account. Since Mahaska County property taxes are due by December 31st each year, your lender will pay the full annual amount on your behalf before this deadline. Lenders usually collect 1/12th of your estimated annual property tax each month, plus a small cushion to account for potential rate increases.

Your lender is required to provide an annual escrow analysis showing how your tax payments were handled and any adjustments needed for the coming year. If property tax rates increase significantly following the March 31, 2025 hearing, you may see an adjustment in your monthly escrow payment. You can verify that your taxes were paid correctly by checking with the Mahaska County Treasurer's office or accessing their online payment system. If you pay taxes directly (without escrow), remember that the December 31st deadline is firm, and late payments will incur penalties and interest charges.

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 Mahaska County? A: Property taxes are due by December 31st each year. For FY 2026 (tax year 2025), taxes will be due by December 31, 2025.

Q: What tax credits are available and how do I apply? A: Available credits include the Homestead Credit (for owner-occupied homes), Disabled Veteran Homestead Credit, and 65+ Homestead Exemption. All credits require application by the July 1st deadline. Applications filed after July 1st will be applied to the following assessment year, not the current year.

Q: How does the Homestead Credit work? A: The Homestead Credit limits annual assessment increases on your primary residence, typically capping growth at around 3-4% per year regardless of market value increases. This is a credit that reduces your tax bill, not an exemption that reduces assessed value. You must apply annually by July 1st.

Q: Is there a property tax exemption for disabled veterans? A: Yes, Iowa provides a 100% property tax exemption for service-disabled Iowa veterans. You must provide a copy of your disability documentation and apply through the county assessor's office by the July 1st deadline.

Q: When are properties reassessed? A: Iowa conducts property reassessments on a rolling schedule. Contact the Mahaska County Assessor's office for specific reassessment years and appeal procedures if you disagree with your assessment.

Q: What happens if I pay my taxes late? A: Late payments after December 31st incur penalties and interest charges. The exact penalty structure is set by Iowa state law and compound over time.

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

Q: Why do tax rates vary within Mahaska County? A: Different areas of the county are served by different school districts, cities, fire departments, library districts, and other special taxing authorities. Your total tax rate is the combination of all taxing districts that serve your specific property location.

Q: When will the final tax rates for 2025 be announced? A: The Mahaska County Board of Supervisors will hold a public hearing on March 31, 2025, at 6:30 PM to set the final property tax levy for FY 2026. Final rates will be announced after this hearing.

Q: Do I automatically receive available tax credits? A: No, most tax credits require annual application by July 1st. Credits are not automatic and must be renewed each year to continue receiving the benefit.

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