I looked up what eBay says (it's ambiguous):
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Sellers' tax responsibilities
You are responsible for paying all fees and taxes associated with using eBay as an eBay seller.
Your tax-related responsibilities may include:
- Paying sales tax on eBay sales
eBay sales tax collection
Based on applicable tax laws, eBay will calculate, collect, and remit sales tax on behalf of sellers for items shipped to customers in the following states and territories (Mississippi is included in the list):
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When a buyer purchases an item on eBay, and the ship to address is one of the above states, eBay will calculate and add the applicable sales tax at checkout. The buyer will pay both the cost of the item along with the sales tax. eBay will collect and remit the tax.
Sellers are not able to opt out of selling items into the states listed above or opt out of eBay automatically collecting sales tax.
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But then it says:
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Top Takeaway
When you list your item you need to indicate that you charge sales tax in the listing form. It's up to you to pay applicable taxes on eBay sales.
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Taxes and import charges