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Updated 2025 Tax Year

Lake County
Property Tax Guide

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

10 Official Sources
8 min read
Quick Facts
Tax Rate
0.8% to 1.4% of market value (varies by taxing districts including school, fire, and local improvement districts)
1st Due
Nov 30
2nd Due
May 31
Exemptions
4+ Available
Section 1

How Property Tax Works

Lake County, Montana operates under the state's property tax system to fund essential local services including schools, roads, fire protection, and county operations. Property taxes are calculated based on assessed value multiplied by the applicable mill levy rate, which varies significantly by location within the county due to special taxing districts such as school districts, fire districts, and other local improvement districts.

Montana implemented significant property tax changes in 2025, affecting how taxes are calculated for different property types. The effective tax rate in Lake County typically ranges from approximately 0.8% to 1.4% of market value, depending on your specific location and the combination of taxing districts that serve your property. Your actual rate will depend on which school district, fire district, and other special districts your property falls within, making location a critical factor in determining your total property tax burden.

Section 2

What Makes Up Your Tax Bill

The following represents typical components of property tax rates in Lake County for levy year 2025, though actual rates vary by specific taxing districts:

ComponentApproximate Rate (Mills)Description
County General15-25Basic county services and operations
School District80-120K-12 education funding (varies by district)
Fire District10-20Fire protection and emergency services
Road District5-15Road maintenance and improvements
Airport District2-5Airport operations (where applicable)
Weed District1-3Noxious weed control
Total Range113-188 MillsEquivalent to 1.13% - 1.88% of assessed value

Note: These rates are estimates and actual millage rates vary significantly based on your property's location within specific taxing districts. For exact rates applicable to your property, contact the Lake County Assessor's Office or check your most recent property tax statement.

Section 3

When Are Property Taxes Due?

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

First Installment
Nov 30
Delinquent after Dec 10
Second Installment
May 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 Lake County are triggered by changes in property ownership or value during the tax year, most commonly due to new construction, major improvements, or change of ownership that affects the property's assessed value. When these events occur, the county may issue a supplemental tax bill to account for the increased assessed value for the remainder of the current tax year.

The supplemental tax is calculated by determining the difference between the new assessed value and the previous assessed value, then applying the current mill levy rate to that difference, prorated for the remaining months in the tax year. For example, if you complete a $100,000 home addition in July, and your property is assessed at the state rate of approximately 100% of market value for residential property, the additional assessed value would be $100,000. With a total mill levy of 150 mills (15%), your supplemental tax would be approximately $1,500, prorated for the remaining 5 months of the tax year, resulting in a supplemental bill of roughly $625.

Example Calculation

The following examples show property tax calculations for Lake County properties, assuming a combined mill levy of 140 mills (14%) and applicable tax credits that require application:

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (100%): $300,000
  • Less: Homestead Tax Credit (if applied): -$1,500
  • Net Taxable Value: $298,500
  • Annual Tax (140 mills): $4,179
  • Monthly Escrow: $348

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (100%): $600,000
  • Less: Homestead Tax Credit (if applied): -$1,500
  • Net Taxable Value: $598,500
  • Annual Tax (140 mills): $8,379
  • Monthly Escrow: $698

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (100%): $1,000,000
  • Less: Homestead Tax Credit (if applied): -$1,500
  • Net Taxable Value: $998,500
  • Annual Tax (140 mills): $13,979
  • Monthly Escrow: $1,165

Note: These examples use estimated rates and credits. Actual calculations depend on your specific location's mill levy and successful application for available tax credits.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Lake County require property tax escrow accounts to ensure timely payment of property taxes. Your lender collects 1/12 of your estimated annual property tax bill with each monthly mortgage payment, holding these funds in an escrow account. Lake County property taxes are due semi-annually on November 30th and May 31st, and your lender will pay these bills directly from your escrow account.

Lenders are required to conduct annual escrow analyses to ensure adequate funds are being collected. If your property taxes increase due to reassessment or mill levy changes, your monthly escrow payment may increase accordingly. You'll receive an annual escrow statement showing all deposits and payments, and any shortage or surplus will be addressed through adjusted monthly payments or refund checks. It's important to review your property tax statements even when using escrow to verify accuracy and ensure your lender is paying the correct amounts on time.

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 Lake County for the current fiscal year? A: Property taxes are due semi-annually on November 30th and May 31st each year. Late payments incur penalties and interest charges.

Q: What tax credits are available and do I need to apply? A: Montana offers several tax credits including the Homestead Tax Credit for qualifying homeowners. Most credits require annual application by March 1st and are NOT automatic. Contact the Lake County Assessor's Office for application forms and eligibility requirements.

Q: How does the Homestead Tax Credit work? A: The Homestead Tax Credit provides property tax relief for qualifying homeowners but requires annual application by March 1st. It functions as a credit against your tax bill, not a reduction in assessed value, and helps limit assessment increases for long-term residents.

Q: How often are properties reassessed in Lake County? A: Montana law requires property to be assessed annually, though physical inspections may not occur every year. The county assessor determines market value based on sales data, cost approaches, and income methods where applicable.

Q: How do I appeal my property assessment? A: Assessment appeals must be filed with the Lake County Tax Appeal Board by the third Monday in June. You'll need to provide evidence supporting your claim that the assessed value exceeds market value.

Q: What penalties apply for late property tax payments? A: Late payments incur penalties and interest charges. Taxes become delinquent after the due date, and properties may eventually face tax lien sales if taxes remain unpaid for extended periods.

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

Q: Why do property tax rates vary within Lake County? A: Tax rates vary based on the specific combination of taxing districts serving your property, including different school districts, fire districts, road districts, and other special assessment districts.

Q: What triggers a supplemental tax assessment? A: New construction, major improvements, change of ownership, or other events that increase property value during the tax year may trigger supplemental assessments and additional tax bills.

Q: Are there tax credits for seniors, veterans, or disabled persons? A: Montana offers various tax credits for qualifying seniors, veterans, and disabled persons. These require separate applications with specific deadlines and eligibility criteria. Contact the Lake County Assessor's Office for detailed information and application forms.

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