Sales tax calculator
The highest combined sales tax in the US is 10.25% in parts of California. The lowest is 0% in five states (Alaska, Delaware, Montana, New Hampshire, Oregon). On a $30,000 vehicle, that's the difference between paying $3,075 in tax and $0. Some people drive hours to buy cars in Oregon for exactly this reason.
Good to know
Combined rates are the real number. State sales tax is just the start. Cities, counties, and special districts add more. California's state rate is 7.25%, but total rates reach 10.25% in some cities. Always look up combined rates for accuracy.
Tax-free shopping still exists. Oregon, Montana, Delaware, New Hampshire, and most of Alaska have no sales tax. For large purchases (cars, furniture), driving to a tax-free state can save thousands. But you may owe "use tax" when you bring the item home.
Online shopping is no longer tax-free. After the 2018 Wayfair Supreme Court decision, states can require online retailers to collect sales tax. Most major retailers now collect based on shipping address. The era of tax-free Amazon is over.
Disclaimers & sources
For estimates only. Not tax advice. Rates vary by location and item.