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Updated 2025 Tax Year

Slope County
Property Tax Guide

Everything you need to know about property taxes in Slope County, ND. 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
Varies by taxing district within Slope County, includes school, fire, and local service districts
1st Due
Dec 26
Exemptions
4+ Available
Section 1

How Property Tax Works

Slope County, North Dakota operates under a property tax system that funds essential local services including schools, roads, emergency services, and county operations. The county assessor values all taxable property annually at its full and true value, with different assessment ratios applied: 91% for commercial property, 93% for residential property, and 95% for agricultural property. Property owners receive tax statements by December 26th each year, with payment options available.

The effective property tax rates in Slope County vary significantly depending on your specific location within the county due to different special taxing districts, including school districts, fire districts, and other local service areas. While North Dakota's statewide average property tax rate is approximately 1%, your actual rate in Slope County will depend on which combination of taxing districts serve your property. The county assessor must notify property owners when valuations increase more than 10% of true and full value and $3,000 or more, providing transparency in the assessment process.

Section 2

What Makes Up Your Tax Bill

ComponentAssessment RatioDescription
Residential Property93%Applied to homes and residential structures
Commercial Property91%Applied to business and commercial buildings
Agricultural Property95%Applied to farms and agricultural land
County General FundVaries by districtFunds county operations and services
School District LevyVaries by districtFunds local school operations and facilities
Special DistrictsVaries by districtFire protection, water, and other local services

Note: Specific mill levy rates vary by fiscal year and taxing district. The assessment ratios listed above are current rates, but 2025 property tax rates are not yet available. Contact the Slope County Assessor for the most current levy rates applicable to your specific property location and the fiscal year in question.

Section 3

When Are Property Taxes Due?

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

First Installment
Dec 26
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 Slope County are triggered by changes in property ownership, new construction, or significant improvements that occur after the annual assessment date. These taxes represent the difference between what was originally assessed and what should have been assessed based on the property changes. The supplemental tax is calculated by applying the current tax rate to the difference in assessed value, then prorated based on the number of months remaining in the tax year.

For example, if you complete a $100,000 home addition in March and your residential assessment ratio is 93%, the additional assessed value would be $93,000. If your combined tax rate is 150 mills (15%), the additional annual tax would be $1,395. Since 9 months remain in the tax year (April through December), your supplemental tax bill would be approximately $1,046 ($1,395 × 9/12 months).

Example Calculation

Example 1: $300,000 Residential Property

  • Market Value: $300,000
  • Assessed Value (93%): $279,000
  • Less: Homestead Credit (if applicable): Varies
  • Net Taxable Value: $279,000 (assuming no credits applied)
  • Estimated Annual Tax (at 15% mill rate): $4,185
  • Monthly Escrow: $349

Example 2: $600,000 Residential Property

  • Market Value: $600,000
  • Assessed Value (93%): $558,000
  • Less: Homestead Credit (if applicable): Varies
  • Net Taxable Value: $558,000 (assuming no credits applied)
  • Estimated Annual Tax (at 15% mill rate): $8,370
  • Monthly Escrow: $698

Example 3: $1,000,000 Commercial Property

  • Market Value: $1,000,000
  • Assessed Value (91%): $910,000
  • Less: Available Credits (if applicable): Varies
  • Net Taxable Value: $910,000 (assuming no credits applied)
  • Estimated Annual Tax (at 15% mill rate): $13,650
  • Monthly Escrow: $1,138

Note: Tax credits require separate application and are not automatically applied. Actual rates vary by specific taxing districts within Slope County.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Slope County require property tax escrow accounts to ensure timely payment of property taxes. Your lender collects monthly payments equal to 1/12 of your estimated annual property tax bill, plus a small cushion as allowed by federal law. The escrow account pays your property taxes when they become due on February 15th and June 15th each year.

Lenders must provide annual escrow statements showing all deposits, payments, and account balances. If you choose to pay property taxes yourself rather than through escrow, you can take advantage of the 5% discount by paying the full amount by February 15th. Property owners should verify that their lender has received and paid tax bills correctly, as you remain ultimately responsible for ensuring taxes are paid even when using an escrow account. Contact the Slope County Treasurer's office to confirm payment status if you have concerns about your escrow payments.

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 Slope County? A: Tax statements are mailed by December 26th annually. The first payment is due February 15th, and the second payment is due June 15th. A 5% discount is available if you pay the full amount by February 15th.

Q: What tax credits are available and how do I apply? A: Contact the Slope County Assessor's office to learn about available tax credits for your specific situation. Most credits require separate application and are not automatically applied to your assessment.

Q: How does the homestead credit work? A: Homestead credits typically limit assessment increases rather than reducing market value. These credits require application and have specific eligibility requirements. Contact your county assessor for current homestead programs and application procedures.

Q: How often are properties reassessed? A: The Slope County Assessor values all taxable property annually at its full and true value. You'll be notified if your valuation increases more than 10% of true and full value and $3,000 or more.

Q: How do I appeal my property assessment? A: If you believe your assessment is excessive and doesn't represent true and full value, contact the Slope County Assessor immediately to request a review of your assessment.

Q: What are the penalties for late payment? A: Contact the Slope County Treasurer's office for specific information about late payment penalties and interest charges.

Q: Can I pay property taxes online? A: Contact the Slope County Treasurer's office to inquire about available online payment options and accepted payment methods.

Q: Why do tax rates vary within Slope County? A: Property tax rates vary based on the specific combination of taxing districts that serve your property, including school districts, fire districts, and other special service areas. Your exact location determines which districts apply to your property.

Verified Sources

Backed by 10 Official Government Sources

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

01
County
June 5, 2024 Regular Meeting Slope County Commissionslopecountynd.gov
02
Tax Doc
2022 Property Tax Statistical Reporttax.nd.gov
03
County
Treasurer - Slope County, NDslopecountynd.gov
04
2025 - RANSOM - DOPP.pdftax.nd.gov
05
County
Slope County, NDslopecountynd.gov
06
Slope Protectionbismarcknd.gov
07
County
Tax Director - Slope County, NDslopecountynd.gov
08
the 2024 Red Book PDFtax.nd.gov
09
County
Slope Countynd.gov
10
State
State Tax Classjeffco.us
All sources verified as of 2025 Tax Year

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