Short answer
The platforms do not require one, but your business still exists in the real world. The location you operate from keeps its normal registration rules, often including a home occupation permit, and certain product categories like food or cosmetics carry their own requirements. Marketplace facilitator laws handle much of the sales tax, not the licensing.
Selling on Etsy, Amazon, eBay, or similar platforms does not itself require a license, none of the major marketplaces demand one to open a shop, but your business still exists in the real world. The location you operate from keeps its normal registration rules, your products keep their regulatory rules, and tax registration follows its own track.
What the platform does and does not change
Marketplaces handle one compliance burden well: most now collect and remit sales tax on marketplace orders under marketplace facilitator laws, which removes much of the sales tax work for platform-only sellers. They change nothing else. If your city requires business registration, a marketplace seller operating from home there needs it, often with a home occupation permit. If your state requires a general license, it applies. If you also sell through your own website, sales tax registration can come back into play under economic nexus rules.
Product rules ride along
Certain product categories carry their own requirements regardless of the sales channel: food and cottage food rules, cosmetics, alcohol, plants and seeds, secondhand goods in some cities, and anything age-restricted. Cottage food laws in particular vary widely on what home kitchens can sell and where. Check your product category against your state's rules, then square away the local layer. The state summaries are the starting point, and our licensing team can map a seller's full stack.
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