HonestCasa logoHonestCasa
All Tax Guides
Updated 2025 Tax Year

Custer County
Property Tax Guide

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

8 Official Sources
8 min read
Calculate Your True CostMortgage Calculator
Quick Facts
Tax Rate
0.350%-0.515% (varies by special taxing districts), general rate 0.385%
Exemptions
5+ Available
Section 1

How Property Tax Works

Custer County, Idaho operates on a property tax system that funds essential local services including schools, roads, fire protection, and county operations. Property taxes are calculated based on assessed value multiplied by the applicable tax rate, which varies significantly depending on your property's location within the county due to different special taxing districts.

For the current tax year, Custer County property tax rates range from 0.350% for rural properties to 0.515% for urban properties, with a general property tax rate of 0.385%. However, your actual effective rate will depend on which special districts serve your property, such as school districts, fire districts, highway districts, and other local improvement districts. Property owners should verify their specific rate with the Custer County Assessor's office, as rates are subject to annual adjustments based on local budget requirements and voter-approved levies.

Section 2

What Makes Up Your Tax Bill

ComponentRate RangeDescription
Base County Levy0.350% - 0.515%Varies by urban/rural designation
School DistrictVariesK-12 education funding, varies by district
Fire DistrictVariesFire protection and emergency services
Highway DistrictVariesLocal road maintenance and construction
Cemetery DistrictVariesCemetery maintenance (if applicable)
Total Effective Rate0.350% - 0.515%+Depends on special district combinations

Rates shown are for FY 2025 and are subject to change based on local budgets and voter-approved supplemental levies. Your actual rate depends on which special taxing districts serve your specific property location. Contact the Custer County Assessor at (208) 879-2360 for your property's exact rate calculation.

Section 3

When Are Property Taxes Due?

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

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 Custer County are additional property tax assessments that occur when there are changes to property ownership, new construction, or property improvements completed after the January 1st assessment date. These taxes are calculated based on the difference between the old and new assessed values, prorated for the remaining months in the tax year.

For example, if you complete a $100,000 home addition in March and your property tax rate is 0.515%, you would owe a supplemental tax of approximately $385 ($100,000 × 0.00515 × 9/12 months remaining). Supplemental tax bills are issued separately from regular property tax bills and typically have a 30-day payment deadline from the date of mailing. Property owners who receive supplemental tax bills should contact the Custer County Treasurer's office at (208) 879-2360 for payment options and specific due dates.

Example Calculation

Example 1: $300,000 Rural Property

  • Assessed Value: $300,000
  • Applicable Rate: 0.350% (rural rate)
  • Annual Tax: $1,050
  • Monthly Escrow: $87.50

Example 2: $600,000 Urban Property

  • Assessed Value: $600,000
  • Applicable Rate: 0.515% (urban rate)
  • Annual Tax: $3,090
  • Monthly Escrow: $257.50

Example 3: $1,000,000 Property with General Rate

  • Assessed Value: $1,000,000
  • Applicable Rate: 0.385% (general property rate)
  • Annual Tax: $3,850
  • Monthly Escrow: $320.83

Note: These examples use base county rates only. Actual taxes will be higher due to additional special district assessments. Property tax credits may be available to qualified homeowners but require separate application to the County Assessor's office.

See How Taxes Affect Your Payment

Property taxes are just part of your total monthly cost. Get the full picture.

Calculate Now
Section 5

Escrow & Property Taxes

Most mortgage lenders in Custer County require property tax escrow accounts to ensure timely payment of property taxes. Your lender collects monthly payments equal to 1/12th of your annual property tax bill plus any required cushion (typically 2-6 months of payments). The lender then pays your property taxes directly to Custer County on the November 30th and May 31st due dates.

Homeowners should verify that their lender has current tax information by reviewing their annual escrow analysis statement and confirming payment with the Custer County Treasurer's office. If your property taxes increase due to reassessment or new special district levies, your monthly escrow payment will be adjusted accordingly. Property owners without escrow accounts are responsible for making direct payments to the Treasurer's office by the specified due dates to avoid 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 Custer County? A: Real estate taxes are paid in two installments: first installment due November 30th and second installment due May 31st. Tax bills are mailed in October each year.

Q: What property tax credits are available in Custer County? A: Idaho offers several tax credits including the Homeowner's Exemption for primary residences. These credits reduce your tax bill but require annual application to the County Assessor's office. Contact (208) 879-2360 for available credits and application requirements.

Q: How does the Homestead Exemption work? A: Idaho's Homestead Exemption caps the annual increase in your home's taxable value, not the market value. You must apply with the Assessor's office and meet residency requirements. This is a tax credit that requires application - it is not automatic.

Q: When are properties reassessed? A: Idaho law requires properties to be assessed annually at market value as of January 1st. Assessment notices are typically mailed in April with appeal deadlines in mid-June.

Q: What are the penalties for late payment? A: Late payments incur interest and penalties. Contact the Treasurer's office at (208) 879-2360 for current penalty rates and payment options.

Q: Can I pay property taxes online? A: Contact the Custer County Treasurer's office at (208) 879-2360 to inquire about online payment options and accepted payment methods.

Q: How do special districts affect my tax rate? A: Your property may be subject to additional taxes from school districts, fire districts, highway districts, and other special assessment areas. These vary by location within the county and can significantly impact your total tax rate.

Q: How do I appeal my property assessment? A: Property assessment appeals must be filed with the Custer County Board of Equalization by the deadline specified on your assessment notice, typically in mid-June. Contact the Assessor's office for appeal forms and procedures.

Verified Sources

Backed by 8 Official Government Sources

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

01
Tax Doc
2025 average property tax ratestax.idaho.gov
02
Treasurercustercountymt.gov
03
State
Certification of Levy Rates - Idaho State Tax Commissiontax.idaho.gov
04
Search Category: Property Appraisaltax.idaho.gov
05
State
Homeowners Guide - Idaho State Tax Commissiontax.idaho.gov
06
judicial nominating election ballotbuttecountyid.us
07
County
Custer County Treasurercustercountyne.gov
08
September 27, 2006 Testimony of Carole King, 29-year ...energy.senate.gov
All sources verified as of 2025 Tax Year

See the Full Picture of Your Home Costs

Property taxes are just one piece of homeownership. HonestCasa helps you understand your total monthly cost and explore safe ways to access your home equity.

Total Monthly Cost

Mortgage + taxes + insurance + HOA

Equity Growth

Track how your equity grows over time

Safe Equity Access

Options for projects or debt payoff

Run Your ScenarioTry Calculator

Free • No credit check • 2-minute estimate