Property Tax in Ada County, Idaho (2026)
Last reviewed:
| Area | Effective Rate | Tax on $300K Home | Tax on $500K Home |
|---|---|---|---|
| Ada County, ID | 0.56% | $1680 | $2800 |
| Idaho average | 0.51% | $1530 | $2550 |
| US national average | 1.10% | $3,300 | $5,500 |
Data sources: US Census Bureau ACS 5-Year Estimates, Tax Foundation, ATTOM Data Solutions
How Property Taxes Work in Ada County
Ada County, Idaho applies an effective property tax rate of 0.56% to assessed home values. This is below the national average of 1.10% and above the Idaho state average of 0.51%. On a home valued at the county median of $476000, a homeowner pays approximately $2643 per year — or $220.25 per month.
Property taxes in Idaho are administered at the county or municipal level. Rates reflect a millage rate applied to assessed value, which may be 50–100% of market value depending on local assessment practices. Many counties offer homestead exemptions, senior exemptions, disability exemptions, and veteran exemptions that can reduce the taxable assessed value — and therefore the effective rate shown above.
What Your Property Tax Funds
Property tax revenue in Ada County funds local public schools, county government operations, road maintenance, emergency services (fire, EMS, police), parks, libraries, and other local services. The distribution among these uses varies by jurisdiction and year based on approved budgets and levies.
How to Appeal Your Assessment
If you believe your property is assessed above its fair market value, you can file an appeal with the Ada County Assessor or Board of Review. Most jurisdictions have a formal appeals process with specific deadlines — typically 30–90 days after assessment notices are mailed. Successful appeals can meaningfully reduce your property tax bill for the current and future tax years.
Frequently Asked Questions
What is the property tax rate in Ada County, Idaho?
The effective property tax rate in Ada County is 0.56% of assessed home value. On the median home value of $476000, homeowners pay approximately $2643 per year. Your actual bill depends on your specific assessed value and any exemptions you qualify for.
How much are property taxes on a $400,000 home in Ada County?
At the 0.56% effective rate, a $400,000 home in Ada County would incur approximately $2240 per year in property taxes, or about $186 per month. Use the calculator above to estimate taxes for any home value.
How does Ada County compare to the Idaho state average?
Ada County's 0.56% effective rate is higher than the Idaho state average of 0.51%. Compared to the national average of 1.10%, it is below average.
Are there property tax exemptions available in Ada County?
Most jurisdictions in Idaho offer homestead exemptions for primary residences, senior citizen exemptions for qualifying homeowners, disability exemptions, and veteran exemptions. These can reduce your assessed value and lower your effective tax rate below the area average. Contact the Ada County Assessor's office to learn which exemptions you qualify for and how to apply.