Sales tax used to be the scary part of selling online. Since 2018 it has mostly been handled for you, at least on marketplaces, but the rules are worth understanding, because they explain why the tax appears on your eBay orders, why the marketplace charges you a fee on it, and when you’re on the hook yourself.
Wayfair and economic nexus
Before 2018 a state could only make you collect its sales tax if you had a physical presence there. The Supreme Court’s decision in South Dakota v. Wayfair changed that: states can now require collection from out-of-state sellers who pass an economic nexus threshold, most commonly $100,000 of sales into the state in a year, with some states also using a transaction count and a few using higher amounts.
For most individual resellers that threshold is never reached in any state but their own. But it created a practical problem for small sellers, which the next set of laws solved.
Marketplace facilitator laws
Every state with a sales tax now has a marketplace facilitator law. It makes the marketplace, not the seller, responsible for collecting and remitting sales tax on sales made through it. When you sell on eBay, Etsy, Amazon, Mercari, Poshmark or Depop:
- The marketplace works out the tax for the buyer’s address.
- The marketplace adds it to the buyer’s total and collects it.
- The marketplace remits it to the state.
- You never touch the money and don’t file anything for those sales.
This is why a buyer in Tennessee pays 9.75% on your listing and a buyer in Oregon pays nothing, without you doing a thing.
The fee on the tax
Here’s the part that annoys sellers. eBay charges its final value fee on the total the buyer paid, including the sales tax it collected. On a $48 item with $6 shipping to a buyer paying 7% tax, the order total is $57.78 and the 13.6% fee is charged on all of it, so $0.51 of your fee is fee-on-tax. Mercari and Depop do the same on their percentage. It’s not a large amount per order; it’s a real amount per year, and it’s legal. The eBay fee calculator has a field for the tax so the fee comes out right.
When you collect it yourself
If you sell through your own website, at in-person events, or on a platform that isn’t a marketplace facilitator, then collection is your responsibility in any state where you have nexus. For most small sellers that means:
- Your home state, from the first sale, because physical presence still counts.
- Any other state where you cross its economic threshold.
Register for a sales tax permit in each of those states, collect the combined rate for the buyer’s address, and file on the schedule the state sets, usually monthly, quarterly or annually depending on volume. Most shopping-cart platforms will calculate the rate at checkout; filing is still on you.
State rate versus combined rate
Every state’s statewide rate is on the sales tax calculator. Most buyers pay more than that, because cities, counties and special districts add local rates on top. California’s statewide rate is 7.25%; Los Angeles buyers pay 9.5% or more. Five states have no statewide sales tax at all: Alaska, Delaware, Montana, New Hampshire and Oregon, though Alaska lets its localities charge their own.
The combined rate is what matters at the register. Enter the local part in the calculator’s local rate field, or look up the exact combined rate for an address on the state revenue department’s site.
Backing tax out of a receipt
If you have a receipt total and need the pre-tax price, don’t multiply by the rate and subtract; that overstates the tax. Divide instead:
price before tax = total ÷ (1 + rate)
A $109.25 receipt at 9.25% is $109.25 ÷ 1.0925 = $100.00 before tax, and $9.25 of tax. The calculator’s reverse mode does this, and it’s how you split a thrift-store receipt into cost of goods and tax paid for your books.
Sales tax you pay when sourcing
The sales tax you pay at a thrift store or retail clearance is part of your cost of goods. Include it. In some states you can present a resale certificate and buy inventory tax-free, since the tax will be collected when the item is sold to the end buyer. It’s worth setting up if you source from stores that will honor it; most thrift stores won’t.
What this means for a typical reseller
- On marketplaces: nothing to collect, nothing to file. Keep the marketplace’s statements; they show tax collected in case a state ever asks.
- On your own site: register in your home state at minimum, collect at the combined rate, file on time.
- In your books: record sales tax paid on inventory as cost, and never count marketplace-collected tax as revenue.
Sources
Statewide rates on the calculator are from each state’s revenue department, checked 13 September 2026. The Wayfair decision is South Dakota v. Wayfair, Inc., 585 U.S. 162 (2018). Marketplace facilitator rules for a specific state are on that state’s department of revenue site; eBay’s own explanation is on its sales tax page.