Out-the-door price in Idaho
How Idaho works
- Idaho is a flat 6% state sales tax on vehicles. Local resort-city taxes generally don't apply to cars (McCall and Ketchum exclude them), though Sun Valley's ordinance wasn't checked.
- Your trade-in reduces the taxable amount in Idaho, and so does a manufacturer rebate applied to the price at the sale. A rebate you take as cash doesn't.
- Idaho doc fees are uncapped. It's a dealer charge, it's subject to sales tax, and your paperwork has to list it separately and say so.
- Registering the car: Idaho dealers file your title and collect the sales tax, but registering is legally the owner's job. You can add the registration through ITD online or at your county's DMV office, and some dealers may handle it for you. The calculator includes registration because you'll pay it either way.
Rules last verified Oct 3, 2026. Our methodology.
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What an Idaho advertised price has to include
Idaho's Attorney General requires a dealer's advertised price to include every cost to you at the sale, freight and dealer prep included, except taxes, license and title fees and the doc fee, which can be left out only if the ad states its amount next to the price. The FTC expects more: every fee the dealer charges, the doc fee included, belongs in the advertised price, so only government charges like tax, title and registration can be added on top. That still isn't your out-the-door number; the calculator above adds the rest.
Federal law comes first
The FTC requires a dealer's advertised price to include every fee the dealer charges. Only charges the government requires you to pay, like tax, title and registration, can be left out. Where a state's rules let a dealer leave a fee out, the dealer still has to follow the federal rule, so the fee goes in. The FTC says a state's doc-fee rules can add disclosures, but they don't change the price that has to be advertised. Read the FTC's guidance.
Idaho law and the FTC conflict on the doc fee
Idaho lets a dealer leave its doc fee out of an advertised price if the ad says, next to the price, "PRICE DOES NOT INCLUDE $___ DEALER DOC FEE." The FTC expects every fee a dealer charges to be in the advertised price, and Idaho's own consumer protection law tells its courts to give the FTC's interpretations great weight. Until regulators or the courts settle it, you may see Idaho ads that leave it out. Ask whether a price includes it, and get the out-the-door price in writing.
What the FTC expects in the advertised price
- The doc fee, whatever the dealer calls it (documentation, administration or handling fee), which Idaho doesn't cap
- Freight, delivery and dealer preparation charges
- Any other charge of any nature necessary before delivery
- An electronic filing vendor's fee, if the dealer passes it on
Can still be added on top
- The 6% sales tax
- Title, registration, plate and county fees, and an electric car's or plug-in hybrid's fee
- Optional products you choose to buy, such as a service contract or GAP coverage
- The doc fee amount: Idaho doesn't cap it. The dealer has to list it separately from other fees and tell you it's a dealer document fee subject to sales tax, and show the title fee at exactly the amount the law sets.
- Rebates: the Attorney General's guidelines say an advertised price has to be available to every buyer, not just those who qualify for a special rebate, which matches federal law.
- Price honoring: a dealer has to let you buy every car in an ad at the advertised price, unless the ad says the price applies only to a set number of cars.
More in our guide: Do dealers have to put fees in the advertised price? What actually changed for 2026
See every state: Which states let dealers leave the doc fee out of the advertised price?
Idaho in detail
Idaho OTD questions, answered
Does a trade-in reduce sales tax in Idaho?
Yes — Idaho taxes the difference: your trade-in's value is subtracted before tax is computed.
Are manufacturer rebates taxed in Idaho?
No — rebates passed to you are treated like a cash discount and reduce the taxable amount.
Is the doc fee capped in Idaho?
No — doc fees are uncapped in Idaho; buyers report a typical $400.00. It's negotiable as part of your total OTD.
What does an Idaho dealer's advertised price have to include?
Every fee the dealer charges, including freight, dealer prep and the doc fee (the FTC's position; Idaho lets dealers leave the doc fee out if the ad states its amount, so the two conflict). Only the 6% sales tax, title, registration and other government fees can be added on top.
Is a manufacturer rebate taxed in Idaho?
Not if it's applied to the price at the sale; Idaho takes it off the taxable amount. If you take the rebate as cash instead, it doesn't reduce the tax.