Idaho Bill of Sale
Idaho keeps it clean: one form both parties sign, one flat 6% tax with no local add-ons, one county assessor visit, and a $3.50 online release that closes the seller's file in five days. ITD 3738 below.
ITD 3738 — both signatures, one page.
Idaho specifics, answered.
What makes ITD 3738 slightly unusual as a bill of sale?
Both parties sign it — many state forms take only the seller's signature, but Idaho wants buyer and seller on the same document. It records the vehicle description, VIN, price, and date; no notarization anywhere in the process.
Where does an Idaho title transfer happen?
At the county assessor's motor vehicle office — Idaho routes titling through assessors rather than a state DMV counter network. The buyer has 30 days; missing it costs a $20 late penalty. (VIN inspections are a separate step, required when a vehicle arrives on an out-of-state title.)
How simple is Idaho's vehicle tax?
About as simple as it gets: a flat 6% statewide with no county or city add-ons on vehicle sales. Gifts skip tax entirely with Form ST-133, the Sales Tax Exemption Certificate, documenting the family transfer.
What's the Idaho seller's five-day duty?
Filing the release of liability — ITD 3858 — within five days of sale, done online for $3.50. It stamps the sale date and buyer into ITD's records so tickets and tolls after the sale land on the right person. Cheap insurance; skip it and the vehicle stays in your name until the buyer gets around to titling.
Not legal advice. Verified against Idaho Transportation Department and State Tax Commission sources in July 2026 — official links in our 50-state requirements table.