Shoppers searching “Boise Ada County sales tax rate” for vehicles still pay Idaho’s statewide 6%—there is no Ada County sales-tax percentage on the ITD vehicle schedule. What Ada adds are admin fees: title total $21.00 ($14 state + $7 county) and registration admin $9.50. On a $30,000 taxable dealer price, sales tax is $1,800.00.
How much is vehicle tax here?
Sales/use is 6% of taxable price unless you qualify for gift, family, or new-resident exemptions. City local option tax (LOT), if any, is user-confirmed—default $0 when none applies. Do not invent an Ada percent.
Dealer $30,000 @ 6%
Ada fee lines
Step-by-step formula
1. Taxable price (dealer inventory trade reduces; private generally no trade reduction).
2. Sales/use = 6% × taxable (unless exempt).
3. Title $21.00; reg admin $9.50; age-band reg $69 / $57 / $45; EMS $1.25.
4. EV extra $140/yr; PHEV $75.
5. Optional LOT only if your city actually imposes it.
Full stack $30,000 age 1–2 yrs
Same with inventory trade cutting $5,000
Trade-in, dealer vs private
Dealer inventory trades can reduce the taxable price. Private purchases generally use 6% use tax without a trade reduction. Doc fees stay in the 6% base per Tax Commission practice in the research pack. Financing at 7.14% APR does not change tax.
Private $30,000
Dealer with trade
No county sales overlay — Ada fees
There is no Ada County sales percentage on vehicles in the ITD schedule. Budget $7 county title admin (inside the $21 total) and $9.50 reg admin.
What Ada adds
LOT reminder
Title and registration fees
Age-band passenger registration: $69 (1–2 years), $57 (3–6), $45 (7+). EV $140; PHEV $75.
Age bands
EV / PHEV extras
Complete worked example
Boise / Ada resident, dealer $30,000, no trade, vehicle age 1–2 years:
$30,000 dealer estimate
EV add-on year
Gifts, family, new residents
Bona fide gift with ST-133GT: sales tax $0. Family sale with prior tax paid + ST-133: $0. New resident who owned the vehicle more than 90 days out of state is often exempt. Fees still apply when you title/register.
Gift ST-133GT
Renewal
What buyers usually mix up
“Boise Ada County sales tax” for vehicles is still Idaho’s statewide 6%. Ada does not add a county sales percent on the ITD vehicle schedule. What changes the cash due are Ada’s admin dollars: title total $21 and registration admin $9.50, plus age-band registration $69 / $57 / $45 and EMS $1.25.
$20,000 @ 6%
Ada admin only
Gift ST-133GT and family ST-133 paths can zero sales tax when paperwork matches Tax Commission rules. New residents who owned the vehicle more than 90 days out of state are often exempt. EV extras are $140; PHEV $75. City LOT stays user-confirmed—default $0 when none applies.
Age-band pick
Gift paperwork
FAQ
Is Boise’s vehicle rate higher than 6%?
Not via an Ada County sales percent on the ITD schedule. Confirm any city LOT separately.
What does Ada actually add?
Dollar admin fees on title and registration.
Are family transfers always free of tax?
Only with the proper ST-133 path and prior tax paid.
Keep official links handy when you title: the agencies named in the references below publish the rate tables and fee charts used on this page. Dealer documentation fees, lender products, and optional plate styles can add more cash at the counter without changing the statutory tax math shown here. If a number in your quote does not match a published line, ask the clerk, treasurer, DMV, or revenue department which official row they used—especially for address-based local rates and annual ownership or valuation taxes.
Estimate hygiene
Financing note
When you compare two counties or two cities, compare the same pieces: purchase tax rate, title, registration base, and any annual ownership/valuation tax. A lower sales-tax city can still cost more once registration fees or valuation taxes are included. Use the worked examples on this page as templates, swap in your price and address rate, and confirm the final bill with the office that collects it.
Before you sign, separate the purchase-tax conversation from the registration conversation. Purchase or use tax is driven by the taxable price and the official locality rate. Registration brings title dollars, plate dollars, and any annual ownership or valuation tax that the state computes from MSRP, factory price, or manufacturer base retail. Keeping those conversations apart is the fastest way to spot a quote that mixed SOT, GST, VLT, or Motor Vehicle Tax into a fake “sales tax” percentage.
Carry the official source links from the reference list into the clerk or treasurer appointment. If a line item cannot be matched to a published table row, fee chart line, or flyer column, ask the office to identify the statute page or bulletin they are using. That single question usually resolves district-boundary mistakes and stale rate printouts.
Renewals follow a shorter path: no new purchase tax when ownership does not change, but the annual registration and ownership or valuation tax still come due on the schedule your state uses. Budget those renewals the same way you budget the first-year stack so a low purchase-tax city does not surprise you later with a high valuation-based renewal.
Conclusion
Price Boise/Ada deals at statewide 6%, add Ada title $21 and reg admin $9.50, then the age-band registration. Skip invented county sales percentages and confirm exemptions on Tax Commission forms.
This page estimates Ada County / Boise vehicle tax and registration amounts from published ITD and Idaho Tax Commission figures. Those agencies set what you actually pay.