What sales tax is and where it applies

Sales tax is a percentage added to the price of goods and services at the point of sale. The seller collects it from you and sends it to the state or local government. The rate varies by state and sometimes by county or city within a state — there is no single national sales tax rate.

Not every purchase is taxed. Most states exempt groceries, prescription medications, and medical equipment. Some states don't tax services like haircuts or car repairs, while others do. A few states have no sales tax at all: Alaska, Delaware, Montana, New Hampshire, and Oregon. If you buy something online from a seller in a state with no sales tax, you may still owe sales tax in your own state, depending on your state's rules.

The tax you pay at checkout is the combined rate of state tax plus any local tax that applies to your address. If you live in a city or county that adds its own tax on top of the state rate, both are included in the total.

Key Takeaways

  • Sales tax is calculated by multiplying the item price by the tax rate as a decimal — a 7% tax on a $100 item means $100 × 0.07 = $7 in tax.
  • Your total tax rate is the state rate plus any local (city or county) rate that applies to your address, and rates vary widely by location.
  • Groceries, prescription drugs, and medical devices are exempt from sales tax in most states, but the rules differ by state.
  • Online purchases are subject to sales tax in your state if the seller has a physical presence there or if your state requires it; the seller should charge it at checkout.

How to calculate sales tax on a single item

To find the sales tax on one purchase, multiply the price before tax by the tax rate expressed as a decimal. If the item costs $50 and the sales tax rate is 8%, convert 8% to 0.08, then multiply: $50 × 0.08 = $4. The tax is $4, and your total is $54.

If you know the total price after tax and want to work backward to find the tax amount, subtract the original price from the total. If you paid $54 total and the item was $50, the tax is $54 − $50 = $4.

Most receipts show the tax amount separately, so you don't have to calculate it yourself. But knowing how to do it helps you understand what you're paying and check whether the amount is correct.

Finding your local sales tax rate

Your sales tax rate depends on where you live and where you make the purchase. If you buy something in a store, the rate that applies is the one for that store's location. If you buy online, the rate depends on your shipping address in most cases.

To find your rate, search "[your state] sales tax rate" or "[your city] sales tax rate" online. Your state's department of revenue or taxation website lists the state rate and explains local rates. Many states also provide a tax rate lookup tool where you enter your zip code and see the combined rate.

Rates change occasionally, so if you're planning a large purchase or need the rate for budgeting, check the official state source rather than relying on a rate you found months ago. Local rates can change when a city or county passes a new tax measure.

Sales tax on multiple items and total purchases

When you buy several items, you can calculate the total tax two ways. The first way: add up all the item prices, then multiply by the tax rate. If you buy items for $30, $20, and $15 (total $65) and the tax rate is 7%, the tax is $65 × 0.07 = $4.55.

The second way: calculate tax on each item separately, then add the taxes together. $30 × 0.07 = $2.10, $20 × 0.07 = $1.40, $15 × 0.07 = $1.05. Total tax: $2.10 + $1.40 + $1.05 = $4.55. Both methods give the same answer.

In real life, your receipt does the math for you. But if you're budgeting for a shopping trip or checking a receipt for errors, either method works. Rounding differences of a penny or two are normal because tax is calculated on each item and then rounded.

What is and isn't taxed

Most states exempt groceries — unprepared food you cook at home — from sales tax. But prepared food, restaurant meals, and hot food from a deli counter are usually taxed. The line between "grocery" and "prepared" varies by state, so a rotisserie chicken might be taxed in one state and not in another.

Prescription medications are exempt from sales tax in all 50 states. Over-the-counter medicines like cold medicine or pain relievers are taxed in most states, though some exempt them. Medical devices prescribed by a doctor — wheelchairs, hearing aids, diabetic supplies — are often exempt, but the rules depend on your state and the specific item.

Services like haircuts, car repairs, and plumbing are taxed in some states and not in others. Clothing is taxed in most states, though a few exempt it or exempt items below a certain price. If you're unsure whether something is taxed, ask the cashier or check your state's tax rules online.

Sales tax on online and mail orders

Online retailers are required to charge sales tax on orders shipped to your state if they have a physical location in your state or if your state has a law requiring it. Most large online sellers now charge sales tax at checkout based on your shipping address. The tax rate applied is for your destination, not the seller's location.

If an online seller doesn't charge sales tax at checkout, you may owe use tax — a tax on purchases made outside your state for use within it. Use tax is the same rate as sales tax and is owed to your state. Most people don't pay it because it's not enforced on individual purchases, but it is technically owed. Some states ask about it on income tax returns.

If you buy from a small seller or a seller in another country, check whether tax was added before you complete the purchase. The receipt or order confirmation should show the tax amount separately.

Frequently Asked Questions

Is sales tax included in the price shown on the shelf?

No. The shelf price is before tax. Sales tax is added at checkout. This is why the total you pay is higher than the price tag. A few states require stores to show the after-tax price, but most do not.

Do I pay sales tax on used items?

It depends on the state and the seller. Used items sold by a business are usually taxed. Used items sold by a private person (like a garage sale or private car sale) are often not taxed. Check your state's rules for the specific situation.

What if the tax amount on my receipt looks wrong?

Check that the tax rate used matches your location's rate. Verify the calculation by multiplying the subtotal by the tax rate. If the rate or math is wrong, ask the store to correct it. Rounding differences of one or two cents are normal.

Do I owe sales tax on items I buy out of state and bring home?

Technically, you owe use tax to your home state on most out-of-state purchases. In practice, this is rarely enforced for individual shoppers. If you buy a car or make a large purchase out of state, your home state may require you to pay use tax when you register it or report it.

Can I get a sales tax refund?

Most states do not refund sales tax to residents. Some states offer refunds to visitors or businesses under specific circumstances. If you believe you paid tax in error, contact the store or your state's tax department to ask about a refund.