What is the property tax rate in Ada County?

The combined effective property tax rate in Ada County, Idaho is approximately 0.71%.

Ada County Property Tax Calculator (2026) — Idaho Property Tax Almanac

Property Tax in Ada County, 2026

A calculator and field guide for Boise-area homeowners — and for anyone considering a move to Ada County — including Idaho's 100% assessment ratio, the $125,000 Homestead Exemption (Idaho Code §63-602G — lesser of $125K or 50% of MV), the HB 292 of 2023 Homeowner Property Tax Relief Account (state-funded ~$200-500/yr automatic credit, made permanent at $50M/yr by HB 304 of 2025), the parallel School District Facilities Fund ($50M/yr state payment of eligible school bond debt), the Property Tax Reduction (Circuit Breaker §63-705) for 65+/widowed/disabled with HHI ≤ $39,130 ($250-$1,500 refundable), and the $1,500 Veterans Property Tax Reduction (NOT full — Idaho is NOT a categorical full-vet state).

Ada County operates under Idaho's 100% assessment ratio + $125,000 Homestead Exemption system (Idaho Code §63-602G). Owner-occupied primary residences receive an exemption equal to $125,000 OR 50% of market value, whichever is LESSER, applied as a reduction in taxable value. Ada's combined mill levy is approximately 9.30 mills per $1,000 of taxable value, producing typical homestead effective rates around 0.71%. HB 292 of 2023 adds a state-funded credit (~$200-500 typical) automatically on the December tax bill.

How the bill is built

Idaho is a 100% AR state — the assessor sets market value with no AR reduction. For owner-occupied homesteads, subtract $125,000 OR 50% of MV (whichever is lesser) to get taxable value. A $400K homestead: TV = $275K. A $200K homestead: TV = $100K (50% cap). Tax = TV × combined mill levy / 1000. State credits (HB 292, PTR Circuit Breaker, Veterans Reduction) apply to the bill after calculation. Bills issue in November, half due Dec 20 and half June 20.

HB 292 of 2023 was Idaho's response to the 2020-2022 housing boom. Two state-funded mechanisms apply automatically to homesteads: the Homeowner Property Tax Relief Account (~$200-500 December bill credit) and the School District Facilities Fund (state pays eligible school bond debt). HB 304 of 2025 made both permanent at $100M/year combined.

Idaho is NOT a full-vet-exemption state. The Veterans Property Tax Reduction (Idaho Code §63-701) caps at $1,500/year for 100% P&T or IU disabled vets — no income limit, but the ceiling means high-bill Boise/CDA homestead owners still pay the difference. Stack with the $125K Homestead Exemption + HB 292 credit for compounded benefit.

2026 Ada County rate breakdown (combined mill levy per $1,000 of taxable value (100% AR; FMV − $125K Homestead Exemption); HB 292 Homeowner Tax Relief Credit ~$200-500 applied post-bill, Boise district)

Taxing entity	Rate
Ada County combined mill levy (county + city + school district + highway district + library district + ACHD); typical Boise residential tax code area, post 100% AR + $125K Homestead Exemption (Idaho Code §63-602G)	9.3000
Combined total	9.3000

As of April 27, 2026 · From Ada County Assessor.

Note: Ada County is Idaho’s largest county by population (~519,000) and contains Boise, Idaho’s state capital and largest city (~245,000). The Treasure Valley combined statistical area (Ada + Canyon counties, ~770,000 residents) is one of the fastest-growing US metros 2010-2024 — Boise consistently ranked among the top 5 fastest-growing US metro areas by percentage during that period. Ada County alone added ~115,000 residents 2010-2020, then another ~50,000 by 2024 — driving real estate prices upward 80-100% from 2019 to 2022 peak.

Note: Ada County’s 0.71% effective rate reflects Boise-area residential mill levies around 9.3 per $1,000 of taxable value applied to a typical $530,000 homestead with the $125,000 Homestead Exemption applied. The Treasure Valley pre-2020 had effective rates around 0.85% on much lower median home values (~$250K), but the dramatic 2020-2022 home value boom outpaced mill levy reductions, leaving effective rates roughly flat despite the underlying property appreciation. HB 292 of 2023 created the Homeowner Property Tax Relief Account (state-funded direct credit), which applies automatically to the December tax bill — typically a $200-500 reduction for Ada County homeowners.

Note: Boise’s economy is anchored by Boise State University (~26,000 students, home of the celebrated blue Smurf Turf football field — the first non-green football field in NCAA history, installed 1986), Albertsons headquarters (~290 employees in HQ; Albertsons is the second-largest US supermarket chain by sales, behind Kroger), Micron Technology (~7,000 Boise employees; Micron is one of the world’s largest semiconductor memory manufacturers, and Boise hosts its global HQ + a $15B fab expansion announced 2022), and HP Inc. (large Boise R&D + manufacturing presence). The state government is the second-largest local employer.

Deductions and exemptions for 2026

Idaho homeowner relief operates through four mechanisms: the $125,000 Homestead Exemption (applies automatically to all primary residences), HB 292's Homeowner Tax Relief Credit (state-funded, ~$200-500 automatic), the Property Tax Reduction Program / Circuit Breaker (income-tested, $250-$1,500 for 65+/widowed/disabled), and the Veterans Property Tax Reduction (up to $1,500 for 100% disabled vets, no income limit). Idaho is NOT a full-vet-exemption state — the $1,500 ceiling matters for high-bill homesteads.

Homestead Exemption (Idaho Code §63-602G)

Reduces taxable value by the LESSER of $125,000 OR 50% of market value, for owner-occupied primary residences. Examples: $400K home → $125K exemption (cap), TV = $275K. $200K home → $100K exemption (50% cap), TV = $100K. Apply with County Assessor; the homestead must be owner-occupied as primary dwelling on January 1 (or before April 15 if purchased after; later filings prorate). One-time application — auto-renews unless ownership or residency changes. Raised from $100K to $125K effective Jan 1, 2022 (HB 389 of 2021).

HB 292 of 2023 Homeowner Property Tax Relief Account

State-funded direct credit applied automatically to the December tax bill on all homestead-exempted properties — no application required. Typical reduction $200-500/year. HB 304 of 2025 made the funding permanent at $50M/year, plus another $50M/year to a parallel School District Facilities Fund that pays eligible school bond debt (reducing the school levy portion for all property owners with eligible bonds). The credit was Idaho's response to the 2020-2022 housing boom that drove Treasure Valley and Coeur d'Alene home values up 80-100%.

Property Tax Reduction Program (Circuit Breaker, Idaho Code §63-705)

Refundable credit of $250-$1,500 for homeowners 65+ OR widowed OR disabled OR blind OR former POW/hostage with 2025 income (after medical expenses) ≤ $39,130 for 2026 tax year. Home value cap: market value ≤ 200% of county median assessed value. Apply with County Assessor or Idaho State Tax Commission between Jan 1 and Apr 15; annual application required. New online portal at the Tax Commission since 2024. A separate Property Tax Deferral program (income limit ~$61,674) lets seniors defer with a state lien repaid at sale.

Veterans Property Tax Reduction (Idaho Code §63-701 et seq.)

Up to $1,500 maximum tax credit for veterans with 100% service-connected disability OR 100% individual unemployability rating. NO income limit. Apply by April 15 with County Assessor or Idaho State Tax Commission; submit VA disability rating letter + DD-214. P&T disabled: one-time application, auto-renews. Non-P&T 100% disabled / IU: annual application required. Stacks with Homestead Exemption + HB 292 credit — a 100% disabled vet in Boise can bring a typical ~$3,800 bill down to ~$1,800-2,100.

Appealing your assessment

Assessment notices are mailed in early June. Contact the County Assessor's office immediately to request informal review; if unsatisfied, file formal appeal with the County Board of Equalization no later than the FOURTH MONDAY OF JUNE (Idaho Code §63-501A). The BOE meets July-August. Appeal further to the Idaho Board of Tax Appeals within 30 days, then District Court. Idaho's tight ~3-week appeal window catches many homeowners off guard — assessment notices arrive early June and BOE deadline is fourth Monday of June.

Cities and towns in Ada County

Ada County contains 6 incorporated municipalities, ranging from Boise to the smallest village. Search volume for property tax is often city-specific, so here is the complete list — with population from the 2020 US Census, rounded to the nearest 100.

Data: US Census Bureau, 2020 Decennial Census. Populations rounded. Cities marked as "split" straddle a county border — the portion inside Ada County is subject to Ada County's tax rolls, while the portion outside is subject to the adjacent county's.

City or town	Type	Population (2020)
Boise County seat	city	245,000
Meridian	city	134,000
Eagle	city	33,000
Kuna	city	27,000
Star	city	14,000
Garden City	city	12,000

About city-level property tax rates: The rate breakdown and calculator on this page reflect the Boise tax district. Other cities in Ada County may pay into different school districts, city rates, and special districts — so their combined rates can differ, sometimes substantially. Always verify the specific rates for your address with the Ada County Assessor before relying on any estimate.

Frequently asked questions

When are Idaho property taxes due?

Bills are issued in November by the county treasurer. Most counties allow split-payment: first half due December 20, second half due June 20. Late payments accrue 1% per month + 2% penalty. Most homeowners pay through escrow. The HB 292 credit applies automatically to the December bill if your homestead exemption is on file with the County Assessor.

How does Idaho's $125,000 Homestead Exemption work?

The exemption (Idaho Code §63-602G) reduces taxable value by the LESSER of $125,000 OR 50% of market value. A $400K home: $125K exempt, TV = $275K. A $200K home: $100K exempt (50% cap), TV = $100K. Apply once with the County Assessor — auto-renews unless ownership or residency changes. Idaho is a 100% AR state, so the exemption directly reduces taxable value (no AR layer).

What is HB 292 of 2023?

HB 292 was Idaho's response to the 2020-2022 housing boom. It created two state-funded mechanisms: a Homeowner Property Tax Relief Account (~$200-500 automatic credit on the December bill for all homestead-exempted properties) and a School District Facilities Fund (state pays eligible school bond debt, reducing the school levy for all owners with eligible bonds). HB 304 of 2025 made both permanent at $100M/year combined. No application required.

How does the Property Tax Reduction (Circuit Breaker) work?

Refundable credit of $250-$1,500 for homeowners 65+ OR widowed OR disabled OR blind OR former POW with 2025 income (after medical expenses) ≤ $39,130 for 2026. Home value cap: market value ≤ 200% of county median assessed value. Apply with County Assessor or Idaho State Tax Commission between Jan 1 and Apr 15; annual application required. Sliding scale by income — lowest-income filers get the full $1,500.

Why isn't Idaho a full-vet-exemption state?

The Veterans Property Tax Reduction (Idaho Code §63-701) is a $1,500 maximum credit, not a full exemption. A 100% disabled veteran in Boise with a typical ~$3,800 bill still owes ~$2,300 after the credit; in lower-bill rural counties (Bingham ~$1,500), the $1,500 credit approximates full exemption. The benefit has NO income limit (unlike the senior PTR Circuit Breaker), and stacks with the $125K Homestead Exemption + HB 292 credit. Apply by April 15.

About Ada County

Beyond the property tax — a few things you might not know about the place.

Weird fact

The Boise State University football team plays on a BLUE field — the first non-green football field in NCAA Division I-A history (installed 1986, replacing the original green AstroTurf installed 1970). The blue field is officially nicknamed "the Smurf Turf" and is one of the most recognizable college football fields in America. Other schools have since installed colored fields (Eastern Washington has a red field, Central Arkansas has a purple+gray field), but Boise State’s blue field is the original and most televised. The NCAA briefly attempted to ban non-green fields in the early 2000s but backed down after Boise State’s pushback.

Hometown hero

Frank Church

The American politician (1924-1984) — born in Boise — served as US Senator from Idaho (D) from 1957 to 1981, becoming one of the most influential Democratic senators of the Cold War era. Church chaired the 1975 Senate Select Committee to Study Governmental Operations (the "Church Committee"), which exposed widespread CIA, FBI, NSA, and IRS abuses during the 1950s-1960s including domestic spying on civil rights leaders, assassination plots against foreign leaders (Cuba’s Fidel Castro, Congo’s Patrice Lumumba), and warrantless surveillance programs. The Church Committee’s findings led directly to FISA (1978) and significantly reformed US intelligence oversight. Church ran for the 1976 Democratic presidential nomination, finishing 4th. The Frank Church-River of No Return Wilderness (~2.4 million acres in central Idaho — the largest contiguous wilderness in the lower 48 US states) was named for him in 1984.

Biggest annual event

Treefort Music Fest

Held annually for 5 days in late March in downtown Boise since 2012, Treefort Music Fest is one of the largest indie music festivals in the western United States — drawing ~25,000 attendees and ~500 musical acts across ~25 venues. Treefort programs music + a "Yogafort" + "Filmfort" (independent films) + "Storyfort" (literary readings) + "Foodfort" (regional chef demonstrations). Boise also hosts the Boise State Bronco Stadium games (one of the most-televised college football venues in the West), the Idaho Shakespeare Festival (June-September), and the Western Idaho Fair (mid-August at Expo Idaho).

Property Tax in Ada County, 2026