How sales tax works
Sales tax is a percentage added to the price of most goods at checkout. The rate is set by your state, and often a county or city rate is added on top — which is why two towns in the same state can charge different amounts.
South Dakota sales tax at a glance
At South Dakota's 6.4% average combined rate:
| Purchase | Sales tax | Total |
|---|---|---|
| $50 | $3 | $53 |
| $500 | $32 | $532 |
| $5,000 | $320 | $5,320 |
South Dakota vs. its neighbors
On a $1,000 purchase, South Dakota's 6.4% sales tax costs about $64 more than Montana's 0% - worth knowing if you're near the border.
| State | Sales tax rate | $1,000 purchase total |
|---|---|---|
| Montana | 0% | $1,000 |
| Wyoming | 5.44% | $1,054 |
| South Dakota (this page) | 6.4% | $1,064 |
| Iowa | 6.95% | $1,070 |
| Nebraska | 6.95% | $1,070 |
| North Dakota | 7.0% | $1,070 |
| Minnesota | 8.05% | $1,080 |
Frequently asked questions
How do I calculate sales tax?
Multiply the item price by the sales tax rate (as a decimal), then add it to the price. This calculator does it instantly — just enter the amount and pick your state.
Are these rates exact?
They're approximate average combined rates (state + typical local). Your exact rate depends on your city/county, so adjust the rate field if you know your local rate.
Which states have no sales tax?
Delaware, Montana, New Hampshire and Oregon have no statewide sales tax. Alaska has no state sales tax but some local taxes apply.
Can I work out the price before tax?
Yes — if you know the total and the rate, divide the total by (1 + rate/100) to get the pre-tax price.
How does South Dakota sales tax compare to nearby states?
On a $1,000 purchase, South Dakota's 6.4% sales tax costs about $64 more than Montana's 0% - worth knowing if you're near the border.
Rates are approximate average combined estimates — check your local rate for exact figures. Not tax advice.