How NFT Marketplaces Work
How does an NFT marketplace work? Learn how listings, bids, signatures, fees and royalties work, how to spot fake collections and how to trade NFTs more safely.
An NFT marketplace is a website or app where people list, buy and sell non-fungible tokens (NFTs). It shows NFTs that live on a blockchain, matches buyers with sellers, and uses smart contracts to swap the NFT for payment in a single transaction — usually without ever taking custody of your NFTs.
Knowing what actually happens when you click "list" or "buy" makes you much harder to scam. Most NFT losses come not from the marketplaces themselves but from fake collections, phishing sites and signatures people did not understand.
What an NFT Marketplace Actually Does
If you are new to NFTs, start with our explainer on what an NFT is. In short, an NFT is a unique token recorded on a blockchain, often pointing to an image, music file, game item or membership pass. Our article Soulbound Tokens Explained expands on this point.
A marketplace sits on top of those tokens and provides:
- Discovery. Collection pages, search, rankings and filters.
- Order book. A record of listings (asks) and offers (bids).
- Settlement. Smart contracts that transfer the NFT to the buyer and the payment to the seller atomically, meaning both happen or neither does.
- Metadata display. Images, traits and descriptions read from the token's metadata.
Some marketplaces focus on one blockchain, such as Ethereum or Solana, while others aggregate listings from several sources.
How Listing and Buying Work Step by Step
Listing an NFT
- 1Connect your wallet. The site reads which NFTs your address holds.
- 2Approve the collection (first time only). On Ethereum-style chains, you send a transaction that lets the marketplace's contract move NFTs from that collection on your behalf when a sale executes.
- 3Sign the listing. You sign a message stating the price, currency and expiry. This signature is usually stored off-chain by the marketplace and costs no gas.
- 4Wait for a buyer. The NFT stays in your wallet. If you transfer it elsewhere, the listing simply fails.
Buying an NFT
- 1The buyer clicks "buy," and their wallet submits a transaction that includes your signed listing.
- 2The marketplace contract checks the signature, moves the NFT to the buyer and sends payment to the seller, minus fees.
- 3The buyer pays the network fee for that transaction.
Offers and bids
Offers work in reverse: a buyer signs a message offering a price, usually in a wrapped token such as WETH, and the seller accepts it with a transaction. Collection-wide offers let a buyer bid on any NFT in a collection. For a deeper look, see What Is an NFT? Non-Fungible Tokens Explained.
Fees, Royalties and Who Gets Paid
| Cost | Who receives it | Notes |
|---|---|---|
| Marketplace fee | The marketplace | A percentage of the sale price, varies by platform |
| Creator royalty | The creator or project | Optional or enforced depending on platform and collection |
| Network (gas) fee | Validators or miners | Paid in the chain's native coin, varies with demand |
| Approval transaction | Validators or miners | Usually once per collection per marketplace |
Royalties have been a long-running debate. Some marketplaces made them optional to compete on price, while some collections use contract-level rules to restrict trading to platforms that honor royalties. Our guide to NFT royalties covers the trade-offs.
Signatures: The Part Most People Skip
Because listings are signed messages, a malicious site can show you a listing request that looks harmless — sometimes presented as "verify your wallet" or "claim a free mint" — and use your signature to list your NFTs for almost nothing and buy them instantly. Related reading: SocialFi Explained.
Before signing anything on an NFT site:
- Confirm you are on the real domain, reached from a bookmark rather than a link in a message.
- Read what your wallet says you are signing: a listing, an approval or a token permission.
- Be suspicious of any signature you did not expect, especially after a "free mint" or airdrop offer.
Our guide to signing transactions safely explains how to read common signature prompts.
How to Avoid Fake Collections
Anyone can mint a copy of a popular collection with the same images and name. Marketplaces try to flag verified collections, but copies still appear, especially for new projects. We cover this in more detail in Decentralized Identity Explained.
Check these before buying:
- 1Contract address. Match it to the one on the project's official website or verified social account.
- 2Creation date. A "famous" collection created yesterday is a copy.
- 3Volume and holders. Real collections usually have long trading histories and many holders.
- 4Links. The collection page should link to the official site, not a look-alike domain.
- 5Too-good-to-be-true prices. A rare item far below the floor price is often a fake or a trap.
Read more in our article on fake NFT mints and counterfeit collections.
Common Risks to Understand
- Illiquidity. Many NFTs have few buyers. A floor price shown on a page is not a guarantee you can sell at that price.
- Metadata hosting. If an NFT's image is stored on a centralized server that goes offline, the token may point to nothing. Decentralized storage reduces but does not remove this risk.
- Wash trading. Some volume is traders selling to themselves to inflate activity.
- Lingering approvals. Old collection approvals remain active until you revoke them.
- Spam NFTs. Unknown NFTs appearing in your wallet are often bait. See how to recognize spam NFTs and tokens.
Our article How to Use a Solana Wallet Safely expands on this point.
Bottom line
An NFT marketplace is a storefront and a set of contracts that trade NFTs straight from your wallet using approvals and signed messages. That design is efficient, but it means every signature matters. Verify the collection's contract address, use bookmarked sites, read each signature prompt, and revoke approvals you no longer need. For more on digital ownership and on-chain culture, browse our web3 articles.
Frequently asked questions
Does an NFT marketplace hold my NFTs?
On most major marketplaces, no. Your NFTs stay in your own wallet, and the marketplace only gets permission to transfer them when a sale you approved is executed. That is why you sign approvals and listing messages. It is also why phishing sites imitating marketplaces are dangerous: a malicious signature can give them the same permission.
Why did I have to approve a collection before listing?
On Ethereum-style chains, the marketplace's contract needs permission to move NFTs from that collection when a buyer accepts your listing. The approval grants that permission, usually for the whole collection. Only approve on the real marketplace site, and revoke approvals you no longer need.
Are NFT royalties always paid?
Not always. Royalties are a fee intended to go to the creator on secondary sales, but many marketplaces let buyers or sellers choose whether to pay them, and enforcement depends on the marketplace and the collection's contract. Check each marketplace's policy if supporting creators matters to you.
How can I tell if an NFT collection is fake?
Compare the collection's contract address with the one published on the project's official website or verified account. Check the creation date, trading history and number of holders. Copies often reuse the same images and name but have a different contract, few holders and very recent activity.