Idaho Car Sales Tax Calculator
Idaho charges a state vehicle sales/use tax of 6% on a car purchase. On a $20,000 vehicle that is about $1,200.00 in state tax before any local add-ons. Enter your own price below — and your trade-in, if Idaho allows a trade-in credit — to estimate what you'll owe.
Quick answer: Idaho’s state vehicle sales/use tax rate is 6%. Local (county/city) taxes may apply on top.
Estimate your Idaho car sales tax
Enter the vehicle price. If Idaho gives a trade-in tax credit, add your trade-in value to reduce the taxable amount.
State rate only. Many Idaho counties and cities add a local sales tax on top, so your actual total may be higher. Trade-in credit rules vary — confirm eligibility with the official source below.
How Idaho taxes a car purchase
| State vehicle sales/use tax rate | 6% |
| Taxable amount | Price − trade-in credit (where allowed) |
| Local / county tax | Varies by jurisdiction — added on top of the state rate |
Title fee is a flat $14.00 base, plus a county title administration fee of $0–$18.75 (total $14–$32.75 depending on county). The 6% rate is Idaho's state sales/use tax (administered by the Idaho State Tax Commission) and applies to both dealer and private-party purchases. Counties also add a registration administration fee of roughly $3–$14. [Verified 2026-07-13 against the ITD Vehicle Registrations fee page: title $14 base, age-based registration $69/$57/$45, EV +$140, PHEV +$75.]
Sales tax on a used car in Idaho
Idaho applies the same 6% state sales/use tax to a used car as to a new one. On a private-party sale the tax is normally collected when you title and register the vehicle — calculated on the price you paid, minus a trade-in credit where the state allows one, and checked against the vehicle's fair-market value to deter under-reporting.
What this estimate excludes
- Local and district taxes. County, city, and transit taxes are added on top of the Idaho state rate.
- Title, registration, and plate fees. These are separate from sales tax — use the Idaho registration and title-transfer calculators for those.
- Dealer documentation fees. A dealer “doc fee” is charged on top and is often itself taxable.
- Exemptions. Gifts, inheritance, and certain family transfers may be exempt — confirm with Idaho Transportation Department — Vehicle Services.
Official Idaho source
Related Idaho tools & guides
Frequently asked questions
How much is sales tax on a car in Idaho?
The Idaho state vehicle sales/use tax rate is 6%. Multiply it by the taxable purchase price (usually the price minus any trade-in credit). Counties and cities may add a local sales tax on top, so confirm your combined rate with Idaho Transportation Department — Vehicle Services.
Do I pay sales tax when buying a used car from a private seller in Idaho?
In most states, sales or use tax on a private-party vehicle purchase is collected when you title and register the car, not at the point of sale. The rate is generally the same as a dealer sale. Confirm the private-sale rules with Idaho Transportation Department — Vehicle Services.
Does Idaho give a sales tax credit for a trade-in?
Most states tax only the difference between the vehicle price and your trade-in value, which lowers the tax you owe. A handful of states tax the full price with no trade-in credit. Verify Idaho's treatment before you rely on the estimate above.
Are there local or county car sales taxes in Idaho?
Often, yes. The rate shown here is the Idaho state rate only; many counties, cities, and transit districts add a local sales tax on vehicle purchases, so your combined rate can be higher. Idaho Transportation Department — Vehicle Services publishes the official combined rates.
Can you legally avoid sales tax on a used car in Idaho?
The legitimate ways to lower or avoid vehicle sales/use tax in Idaho are a qualifying trade-in credit (where the state allows one), a genuine gift or qualifying family transfer, or a specific exemption the state grants — not understating the sale price, which is illegal and easily caught by Idaho Transportation Department — Vehicle Services against the vehicle's fair-market value. Confirm any exemption with Idaho Transportation Department — Vehicle Services before relying on it.
Last reviewed: 2026-01-01 · Reviewed by the Car Paperwork editorial team · Based on official Idaho Transportation Department — Vehicle Services sources · Independent resource · Not legal advice