Polygon PoS is a low-fee blockchain that works like Ethereum for developers and wallets but runs on its own set of validators. This article explains where it comes from, how it is secured, why its fees are low, and the difference between native and bridged USDC on it.
If terms like "layer 2" are new, see layer 1, layer 2 and layer 3.
What Polygon is and who built it
Polygon began in 2017 as a project called Matic Network, started by a team of developers in India, and was rebranded Polygon in 2021. It is developed by Polygon Labs and a wider community, and governed through a foundation and token holders.
The problem it was made to solve was simple. In 2020 and 2021 Ethereum mainnet became very expensive, and ordinary users could not afford small transactions. Polygon PoS offered the same kind of environment, the EVM, with fees of a small fraction of a cent. Apps could be moved over with few changes, and wallets like MetaMask worked by adding a network.
Today Polygon PoS is used for payments, stablecoin transfers, games, loyalty and consumer apps, and decentralized finance.
How it works: its own validators plus checkpoints
Polygon PoS is a proof-of-stake chain with its own validator set. It is not a rollup. Validators stake the POL token and take turns producing blocks. A new block arrives about every two seconds; the chain page shows the current pace.
The chain has two layers of software. The execution layer produces blocks and is EVM-compatible. A second layer, Heimdall, tracks the validator set and finality. At intervals the chain writes a checkpoint to Ethereum, a compact commitment to its recent history. A checkpoint helps with proving history and with moving funds back to Ethereum. It does not mean Ethereum validates every Polygon transaction.
This is the key difference from a rollup such as Arbitrum: a rollup posts its full transaction data to Ethereum and inherits Ethereum security, while Polygon PoS relies mainly on its own validators and their stake. See rollups: optimistic vs zk.
Finality
A transaction is in a block within seconds. Polygon also has fast finality, where validators confirm blocks in a few seconds without waiting for the Ethereum checkpoint. Short reorganizations of already included blocks have happened in the past and are rare. For large amounts, wait for the finality your service requires. See finality and confirmations.
Fees and the POL token
The gas token is POL. It replaced MATIC as the name and ticker of the token, and it is the token you need to pay for transactions. This is a common mistake: sending tokens on Polygon needs a little POL for gas, not ETH.
Polygon uses the same fee model as Ethereum after EIP-1559: a base fee, which is burnt, plus a priority tip, with the total set by gas used times the price. A transfer usually costs a small fraction of a cent, because blocks are rarely full and the price of POL per unit of gas is low. Fees rise when the network is busy. See the gas tracker for the current number and gas and fees.
Why is it cheap? There is no cost of posting data to Ethereum for every transaction, as rollups have. Blocks are produced by a smaller group of validators, which is cheaper to run than Ethereum's very large set. The trade-off is a different security model, not a free lunch.
Addresses and tokens
Polygon uses 0x addresses, the same as Ethereum and the other EVM chains. Your address on Ethereum is the same on Polygon, but the balances are separate. ERC-20 style tokens exist on Polygon, with their own contract addresses per chain.
Bridged vs native USDC
USDC exists on Polygon in two forms that confuse many people. Native USDC is issued directly on Polygon by Circle, the company behind USDC. An older form, often called bridged USDC (shown as USDC.e), was created when USDC was locked on Ethereum through a bridge and a representation was issued on Polygon. They look similar, but they are different token contracts. Some apps and exchanges accept only one of them, and swapping between them costs a small fee. Always check which contract your app expects. See stablecoins and bridges and their risks.
The wider Polygon ecosystem
Polygon Labs also works on other scaling technology, including zero-knowledge based projects, and talks about connecting many chains together. This article covers only Polygon PoS, the chain you see on ChainMonitor. For other products, see Polygon's own documentation.
How Polygon compares
| Polygon PoS | Ethereum | Arbitrum | Base | |
|---|---|---|---|---|
| Type | Own PoS chain | Layer 1 | Optimistic rollup | Optimistic rollup |
| Gas token | POL | ETH | ETH | ETH |
| Security from | Own validators | Own validators | Ethereum | Ethereum |
| Fees | Very low | Highest | Low | Low |
See why fees differ between chains.
What to watch out for
- Gas token. You need POL, not ETH, for gas. A wallet with USDC but no POL cannot send.
- Wrong network. An address looks the same on all EVM chains, so confirm that the receiver expects Polygon. Exchanges may list "Polygon" and "MATIC" or "POL" differently.
- Different security. Polygon PoS is secured by its own validators. A rollup posts data to Ethereum. For large long-term holdings, understand this difference.
- Bridged tokens. Bridges have been targets of attacks. Prefer native assets and small test transfers.
- Reorgs before finality. Treat very recent blocks as tentative.
Follow Polygon live on ChainMonitor
- Live blocks: tiles of recent blocks with their fill level and fees.
- Recent blocks list and the header search.
- Gas tracker: cost of a POL send, a USDC transfer and a swap now.
- RPC health for Polygon: public endpoints ranked by latency and lag.
Frequently asked questions
Why is Polygon so cheap?
It runs its own chain with its own validators, so it does not pay to post every transaction to Ethereum. Blocks are also rarely full. The trade-off is that it relies on its own validator set for security.
Is Polygon a layer 2?
Polygon PoS is often called a layer 2 or sidechain, but technically it is not a rollup. It checkpoints to Ethereum, but its validators produce and secure blocks.
What is the difference between MATIC and POL?
POL replaced MATIC as the native token of Polygon PoS. It is the token used for gas and for staking.
Do I need ETH to send USDC on Polygon?
No. Gas is paid in POL. You need a small amount of POL in the same wallet.
What is USDC.e?
It is the older, bridged version of USDC on Polygon. Native USDC is issued directly by Circle on Polygon. They are separate tokens.
Is Polygon the same as Ethereum?
No. It uses the same EVM and address format, but it is a separate chain with its own validators, token and fees.