South Dakota Car Sales Tax Calculator

By Mohamed SkhiriUpdated November 7, 2026

Car sales tax in South Dakota: the 4% excise tax

SDCL 32-5B-1 sets a 4% excise tax on the purchase price of any motor vehicle bought for use on South Dakota roads, and says it's charged "in lieu of" the state and municipal sales taxes. Dealers don't collect it. You pay it to the county treasurer when you apply for title and registration. That's also why a South Dakota dealer's buyer's order shows sales tax on add-ons and services but not on the vehicle itself.

Trade-ins count on every sale

Many states limit trade-in credit to dealer sales or new cars. South Dakota doesn't. SDCL 32-5B-4 deducts the trade-in value from the price in all three situations: a new vehicle, a used vehicle from a licensed dealer, and a private sale where a vehicle is taken in trade. In a private deal, buyer and seller list the trade on the bill of sale.

When no excise tax is due

• Old, cheap cars: a vehicle eleven or more model years old sold for $2,500 or less before trade-in.
• Family transfers: transfers without payment between spouses, parent and child, or siblings. The $10 title fee still applies.
• Inheritance: vehicles inherited or left by bequest.
• Returning residents: a former resident coming back with a vehicle they already paid South Dakota excise tax on.
• Tax already paid elsewhere: under SDCL 32-5B-11, no tax is owed if you already paid sales, use or excise tax on the vehicle to South Dakota or another state, as long as that tax was at least as much. Bring a dealer affidavit, bill of sale or receipt as proof. Without proof, the treasurer charges 4% of the vehicle's retail value.

License plate fees by weight and age

Non-commercial plates are priced per month by weight, with a 30% reduction once the vehicle is 10 years or older:

Registrations renew in a month set by the first letter of your last name. A and B renew in January, C–E in February, F, G and J in March, H, I and O in May, K and L in June, M and N in July, P–R in August, S in September and T–Z in November. Pickups over 6,000 lbs may register by gross weight instead. Electric vehicles charged from an external source pay an extra $100 each year.

Title and other fees

The $100 administrative fee applies to people titling a vehicle in South Dakota without a South Dakota driver's license or ID and without a physical South Dakota address. Counties can also add a wheel tax, which the Department of Revenue lists by county.

Worked examples

Deadlines and penalties

Title and register within 45 days of the purchase date. Private sellers must give you a free 45-day seller's permit, and you can buy a 5–15 day permit at $1 a day if you need more time. Interest and penalties are counted from the purchase date:

• After 45 days: interest of 1.25% of the tax or $5, whichever is greater, for the first month, then 1.25% a month
• After 60 days: a one-time penalty of 10% of the tax or $10, whichever is greater
• A late title application penalty of $1 a week past the 45 days, up to $50

Frequently asked questions