What is an NFT Marketplace? A Clear Explanation for Beginners (2026)

An NFT marketplace is where tokens get bought and sold. But the differences between them — fees, royalty policies, who controls what — turned out to matter more than I initially assumed.

When I first started looking into NFTs, I assumed a marketplace was just a marketplace. Like eBay, but for tokens. You list a thing, someone buys it, money changes hands. I didn’t think much about the differences between platforms.

That turned out to be a bit naive. The choice of marketplace affects what fees you pay, whether creators receive royalties, how much custody you have over your own tokens, and in some cases whether a trade can be reversed or not. These aren’t small differences.

Contents

What an NFT Marketplace Actually Does
The Main Types
What Varies Between Platforms
What I Look For Now
Where I’m Still Learning

What an NFT Marketplace Actually Does

At its core, an NFT marketplace connects buyers and sellers of NFTs. It provides a way to list tokens for sale, discover what’s available, and execute transactions. Most marketplaces also handle metadata display — showing the images, names, and traits associated with each token.

The actual transfer of ownership happens on-chain through a smart contract. The marketplace is the interface that makes it usable — it’s not storing your NFTs, it’s providing a front end for the blockchain transactions that move them.

This distinction matters. If a marketplace shuts down, your NFTs don’t disappear — they’re still on-chain. What you lose is access to that particular interface for trading them. You’d need to use a different marketplace or trade directly.

The Main Types

There are broadly two kinds of NFT marketplaces: custodial and non-custodial.

A custodial marketplace holds your assets on your behalf — similar to how a centralised exchange holds your crypto. You log in with an email, and the platform manages the keys. It’s easier to get started, but you’re trusting the platform with your tokens. If the platform gets hacked or goes bankrupt, your assets are at risk.

A non-custodial marketplace connects directly to your own wallet. You sign transactions yourself. The marketplace never holds your tokens — it only facilitates the trade. This is the model most NFT marketplaces on Polygon use. It requires a wallet to get started, which adds a step — but it means you stay in control of your own assets throughout.

What Varies Between Platforms

Once I started actually using marketplaces rather than just reading about them, the differences became obvious quickly. The main ones:

Fees. Most marketplaces charge a percentage of each sale — typically somewhere between 1% and 5%. Some also charge listing fees. On top of that, you pay gas fees for the on-chain transaction. On Polygon, gas is cheap enough that it’s rarely the main cost. The marketplace fee is usually what matters.

Royalty enforcement. As I wrote about separately, some marketplaces honour creator royalties on secondary sales and some don’t. If you’re a creator, this is one of the most important things to check before choosing where to list.

Liquidity. A marketplace is only useful if there are buyers. A platform with high trading volume gives you a better chance of actually selling something. A platform with low volume might mean your listing sits unseen for months. This is one reason OpenSea has stayed dominant despite its changing policies — it still has the most buyers.

Supported chains. Not every marketplace supports every blockchain. Some are Ethereum-only. Others support Polygon, Solana, and other chains. If you’re working on Polygon, you need to verify the marketplace actually supports Polygon before listing anything there.

My Honest Reflection: I Didn’t Think About This Carefully Enough at First
When I first started exploring NFTs, I just used whatever marketplace came up first in a search. I didn’t think about royalty policies, fee structures, or whether the platform would still exist in a year. I treated all marketplaces as roughly equivalent.

After reading more carefully — especially after understanding how royalty enforcement actually works — I realised the choice matters. Not just for sellers, but for buyers too. If you’re buying an NFT on a platform that doesn’t enforce royalties, the creator you’re ostensibly supporting isn’t actually receiving anything from your purchase. That’s worth knowing. I wish I’d thought about it earlier.

What I Look For Now

When I’m thinking about a marketplace on Polygon, the questions I ask are: Does it enforce royalties? What’s the fee structure? How much trading volume does it actually have? Does it connect to my own wallet or does it hold my assets? And — honestly — how long has it been around, and does it seem like it’ll still exist next year?

That last one sounds cynical, but the NFT marketplace space has had a lot of platforms launch, grab attention, and then quietly reduce activity or shut down. Longevity and sustained volume matter more than features in a press release.

Where I’m Still Learning

I have a reasonable understanding of how NFT marketplaces work in general. What I’m less clear on is the current competitive landscape on Polygon specifically in 2026 — which platforms are most active, which have the best royalty enforcement, and whether any newer platforms have meaningfully changed the dynamics. The space moves faster than I can keep up with comprehensively. If you’re actively using a Polygon marketplace and have opinions on it, I’d genuinely want to hear them.

What is an NFT Marketplace? Where Tokens Get Traded