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Updated 2025 Tax Year

Boundary County
Property Tax Guide

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

9 Official Sources
8 min read
Quick Facts
Tax Rate
0.373% to 0.565% depending on taxing districts (rural vs urban areas)
1st Due
Nov 20
2nd Due
Apr 20
Exemptions
5+ Available
Section 1

How Property Tax Works

Boundary County, Idaho operates a property tax system that funds essential local services including schools, county operations, emergency services, and various special districts. Property taxes are the primary source of revenue for these local government functions, with collections supporting everything from road maintenance to public safety and education.

For the 2025 tax year, property tax rates in Boundary County vary significantly by location, ranging from approximately 0.373% in rural areas to 0.565% in urban areas. Your actual tax rate depends on which special taxing districts serve your property, such as school districts, highway districts, fire districts, and municipal services. Properties within city limits typically face higher rates due to additional municipal levies, while rural properties may have fewer overlapping districts but could include special assessments for services like fire protection or cemetery districts.

The county uses a market value assessment system where properties are assessed at current market value, with taxes calculated by applying the local tax rate to the assessed value minus any applicable tax credits. Most tax credits and exemptions require annual application and are not automatically applied to your property tax bill.

Section 2

What Makes Up Your Tax Bill

ComponentRate RangeDescription
County General~0.150%Basic county operations, roads, public safety
School District~0.180-0.250%Local school funding, varies by district
Highway District~0.050-0.080%Road maintenance and construction
Fire District~0.030-0.060%Fire protection services (rural areas)
Cemetery District~0.010-0.020%Cemetery maintenance
Municipal~0.100-0.150%City services (urban areas only)
Total Urban~0.565%Properties within city limits
Total Rural~0.373%Properties outside city limits

Rates shown are for FY 2025-2026 levy year and vary by specific location within Boundary County. Your actual rate depends on which special taxing districts serve your property. Contact the Boundary County Assessor for your specific district combination.

Section 3

When Are Property Taxes Due?

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

First Installment
Nov 20
Delinquent after Dec 10
Second Installment
Apr 20
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 are additional property tax bills issued when there's a change in property ownership, completion of new construction, or other improvements that increase assessed value during the tax year. Unlike annual property taxes, supplemental taxes are prorated based on the number of months remaining in the fiscal year when the change occurs.

Common triggers include purchasing a home, completing additions or major renovations, installing significant improvements like pools or outbuildings, or correcting assessment errors. The supplemental tax is calculated by applying the current tax rate to the difference between the old and new assessed values, then prorating for the remaining months.

For example, if you purchase a home in March that was previously assessed at $250,000 but now reflects a market value of $400,000, you would receive a supplemental tax bill for the $150,000 increase, prorated for the 9 remaining months of the fiscal year (April through December). At a 0.565% urban rate, this would result in a supplemental bill of approximately $636 ($150,000 × 0.00565 × 9/12).

Example Calculation

Example 1: $300,000 Home (Rural Area)

  • Market Value: $300,000
  • Homeowner's Exemption: -$125,000 (50% of value, max $125,000)
  • Net Taxable Value: $175,000
  • Tax Rate: 0.373% (rural)
  • Annual Tax: $653
  • Monthly (Escrow): $54

Example 2: $600,000 Home (Urban Area)

  • Market Value: $600,000
  • Homeowner's Exemption: -$125,000 (maximum exemption)
  • Net Taxable Value: $475,000
  • Tax Rate: 0.565% (urban)
  • Annual Tax: $2,684
  • Monthly (Escrow): $224

Example 3: $1,000,000 Home (Urban Area)

  • Market Value: $1,000,000
  • Homeowner's Exemption: -$125,000 (maximum exemption)
  • Net Taxable Value: $875,000
  • Tax Rate: 0.565% (urban)
  • Annual Tax: $4,944
  • Monthly (Escrow): $412

Note: Homeowner's exemption requires annual application and is not automatically applied. Additional credits may be available for qualifying seniors, veterans, or disabled persons.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Boundary County require borrowers to maintain an escrow account for property tax payments, especially when the down payment is less than 20%. Your lender collects monthly payments equal to 1/12th of your estimated annual property tax bill, holds these funds in an escrow account, and pays your taxes directly to the county when due.

Property taxes in Boundary County are due December 20th for real estate, creating a single annual payment cycle. Lenders typically pay this bill in early December to ensure timely payment. Your lender will provide an annual escrow analysis, usually in the fall, showing the previous year's activity and adjusting your monthly payment for the coming year based on any changes in tax assessments or rates.

If your property taxes increase due to rising assessments or new special district levies, your lender may require an escrow shortage payment or spread the shortage over 12 months in addition to the new payment amount. You can verify that your taxes were paid correctly by checking with the Boundary County Treasurer's office or reviewing your property's payment history online.

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 Boundary County? A: Real estate property taxes are due December 20th annually for the current fiscal year. Personal property taxes have different deadlines: declarations are due March 15th and payments are due June 20th.

Q: What homeowner credits are available and how do I apply? A: The primary homeowner's exemption reduces assessed value by 50% of your home's value (maximum $125,000 reduction) and covers up to one acre of land. This requires annual application through the Boundary County Assessor's office and is not automatically applied to your property.

Q: Are there additional tax credits for seniors or veterans? A: Idaho offers various property tax credits including the Circuit Breaker Program for qualifying low-income seniors and disabled persons, and potential veterans' exemptions. All require separate applications with specific income and eligibility requirements. Contact the County Assessor for current application forms and deadlines.

Q: How does the homestead exemption work? A: Idaho's homestead exemption primarily protects against creditors rather than reducing taxes. The property tax benefit comes from the homeowner's exemption described above, which directly reduces your assessed value for tax calculation purposes.

Q: What happens if I pay my taxes late? A: Property taxes not paid by December 20th become delinquent and incur penalties and interest charges. The county may eventually initiate tax deed proceedings for severely delinquent accounts.

Q: Can I pay my property taxes online? A: Contact the Boundary County Treasurer's office to confirm current online payment options and accepted payment methods. Many Idaho counties offer online payment systems for property taxes.

Q: How often are properties reassessed? A: Idaho law requires annual assessment updates to reflect current market values. The County Assessor reviews property values each year, with assessment notices typically mailed in spring.

Q: How do I appeal my property assessment? A: Assessment appeals must be filed with the Boundary County Board of Equalization within 30 days of receiving your assessment notice. The appeal process includes specific deadlines and documentation requirements.

Q: Why do tax rates vary within Boundary County? A: Your tax rate depends on which special taxing districts serve your property. Urban properties typically pay higher rates due to municipal services, while rural properties may have different combinations of fire, highway, and other special districts.

Q: What triggers a supplemental tax bill? A: Supplemental taxes occur when property changes hands, new construction is completed, or significant improvements are made during the tax year. These are prorated based on the remaining months in the fiscal year.

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