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Updated 2025 Tax Year

Harper County
Property Tax Guide

Everything you need to know about property taxes in Harper County, OK. 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
Approximately 0.03% effective rate, varies significantly by taxing district combination
1st Due
Oct 1
Exemptions
4+ Available
Section 1

How Property Tax Works

Harper County, Oklahoma operates on an ad valorem property tax system that funds essential local services including schools, county operations, emergency services, and infrastructure maintenance. Property taxes are levied annually on October 1st based on the assessed value as of January 1st of the same year, covering both real estate and personal property within the county.

The effective property tax rate in Harper County is approximately 0.03% for the 2025 levy year, though actual rates vary significantly by location within the county due to different combinations of special taxing districts. These districts may include school districts, municipal services, fire protection districts, and other local improvement districts. Property owners should verify their specific tax rate based on their exact location and applicable taxing districts, as rates can differ substantially even between neighboring properties.

Property taxes in Harper County are due on November 1st following the October 1st levy date, with the option to pay in two equal installments. The county assessor is required to conduct property revaluations at least once every four years to maintain current market assessments.

Section 2

What Makes Up Your Tax Bill

ComponentRateDescription
Base County LevyVariesGeneral county operations and services
School DistrictVariesLocal school district operations and bonds
Municipal ServicesVariesCity/town services (if applicable)
Special DistrictsVariesFire protection, library, improvement districts
Total Effective Rate~0.03%Combined rate for FY 2025

Note: These rates apply to the 2025 levy year (taxes due November 2025). Actual rates vary significantly by property location within Harper County due to different combinations of special taxing districts. Property owners should contact the Harper County Assessor's office to determine their exact rate based on their specific taxing districts.

The county approved a 1% sales tax, but this does not affect property tax calculations. All special district taxes require separate voter approval and are added to the base county and school district levies.

Section 3

When Are Property Taxes Due?

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

First Installment
Oct 1
Delinquent after Dec 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 Harper County are triggered by changes in property ownership, new construction, or significant improvements that occur after the January 1st assessment date but before the October 1st levy date. These taxes ensure that property changes during the tax year are properly assessed and taxed for the current year.

Supplemental taxes are calculated by applying the current year's tax rate to the difference between the old and new assessed values, prorated for the portion of the tax year remaining after the change occurred. For example, if a property is improved in March, the supplemental tax would cover the increased value for the remaining 9-10 months of the tax year.

Property owners receive a separate supplemental tax bill when these situations occur, which is due 30 days from the date of issuance. This is in addition to the regular annual property tax bill due on November 1st.

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (varies by assessment ratio): $300,000
  • Less: Homestead Credit (if applicable): -$1,000
  • Net Taxable Value: $299,000
  • Annual Tax ($299,000 × 0.03%): $90
  • Monthly Escrow: $7.50

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value: $600,000
  • Less: Homestead Credit (if applicable): -$1,000
  • Net Taxable Value: $599,000
  • Annual Tax ($599,000 × 0.03%): $180
  • Monthly Escrow: $15.00

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value: $1,000,000
  • Less: Homestead Credit (if applicable): -$1,000
  • Net Taxable Value: $999,000
  • Annual Tax ($999,000 × 0.03%): $300
  • Monthly Escrow: $25.00

Note: Tax credits shown require separate application and are not automatically applied. Actual rates may vary by location within the county due to special taxing districts. Contact the Harper County Assessor for specific credits available and application requirements.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Harper County require property tax escrow accounts for borrowers with less than 20% down payment. Lenders collect monthly escrow payments equal to 1/12th of the annual property tax bill, plus insurance premiums. These funds are held in a non-interest bearing account and used to pay taxes when due.

Property taxes are due November 1st annually, and lenders typically pay the full amount by the due date to avoid penalties. Escrow accounts are analyzed annually, and lenders may adjust monthly payments if there's a shortage or surplus. Property owners receive an annual escrow statement showing all deposits and disbursements.

Property owners with escrow accounts should verify that their lender pays taxes on time, as the property owner remains ultimately responsible for tax payments even when using escrow. The Harper County Treasurer's office can confirm payment status, and property owners should contact their lender immediately if taxes appear unpaid after the November 1st due date.

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 Harper County for the current fiscal year? A: Property taxes are due November 1st following the October 1st levy date. For the 2025 levy year, taxes are due November 1, 2025, with the option to pay in two equal installments.

Q: What homestead tax credit is available and how do I apply? A: Oklahoma offers a homestead credit that caps annual assessment increases for primary residences. This credit requires application with the Harper County Assessor's office by March 15th. Applications filed after March 15th will be effective the following tax year. Contact the assessor's office for current application forms and specific credit amounts.

Q: Are there tax credits for senior citizens? A: Yes, Oklahoma provides tax credits for taxpayers age 65 and older. These credits reduce your tax bill and require separate application with documentation of age and income. Contact the Harper County Assessor's office for eligibility requirements and application deadlines.

Q: How often are properties reassessed in Harper County? A: Oklahoma law requires county assessors to revalue all property at least once every four years. The Harper County Assessor may conduct more frequent assessments as needed to maintain current market values.

Q: What happens if I pay my property taxes late? A: Late payments incur penalties and interest charges. Contact the Harper County Treasurer's office for specific penalty rates and payment options if you cannot pay by the November 1st due date.

Q: Can I pay my property taxes online? A: Contact the Harper County Treasurer's office to inquire about online payment options and accepted payment methods. Many Oklahoma counties now offer online payment systems for property taxes.

Q: How do I appeal my property assessment? A: Property owners who disagree with their assessment can file an appeal with the Harper County Board of Equalization. Appeals must typically be filed within a specific timeframe after assessment notices are mailed. Contact the assessor's office for appeal forms and deadlines.

Q: Why did my tax bill increase if the tax rate stayed the same? A: Tax bills can increase due to rising property values, new special district assessments, or expiration of temporary tax credits. Additionally, if you previously received credits that required reapplication and didn't reapply, your bill would increase even with the same tax rate and property value.

Verified Sources

Backed by 10 Official Government Sources

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

01
County
harper county - Oklahoma Digital Prairiedigitalprairie.ok.gov
02
Tax Doc
Sales Tax News Release January 2026 - Oklahoma.govoklahoma.gov
03
County
Harper County Kansas: Homeharpercountyks.gov
04
County
HARPER COUNTY - Oklahoma State Auditor & Inspectorsai.ok.gov
05
County
harper county - Oklahoma Digital Prairiedigitalprairie.ok.gov
06
County
of Harper County, Kansas December 31, 2023 and 2022admin.ks.gov
07
2026-2027 Form 921 Application for Homestead Exemptionoklahoma.gov
08
State
Overview of State Issuesoksenate.gov
09
Bankruptcy Reform Act of 1998; Responsible Borrower ...commdocs.house.gov
10
Oklahoma.gov Homeoklahoma.gov
All sources verified as of 2025 Tax Year

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