Polygon Bridge.

A transfer through the Polygon Bridge is a lock-and-mint operation rather than a swap. On the way in, the deposit contract on Ethereum takes custody of the asset you send and a matching representation appears in your Polygon wallet once the network has registered the deposit. On the way out, the asset is burned on Polygon and the original is released from the Ethereum contract. Nothing changes hands outside those two contracts, which is why the mechanism is described in detail in Polygon's own documentation rather than left to a third party to explain.

How the PoS bridge contract works

The Polygon Bridge for the PoS chain runs two one-way paths. A state sync mechanism carries deposit messages from Ethereum to Polygon quickly, so funds usually show up in well under an hour. The return path is different: Polygon's block producers periodically submit a checkpoint, a compressed proof of recent Polygon blocks, to a contract on Ethereum, and only after that checkpoint lands can a withdrawal be finalized and claimed.

What assets you can move across

ETH, major stablecoins, and most ERC-20 tokens Polygon lists can move through the standard PoS bridge, and the asset keeps the same symbol and decimals on the other side. Some NFT collections use a parallel Plasma bridge path with its own withdrawal rules, so check which contract a given asset uses before assuming the timing described here applies unchanged.

Polygon's native gas token is now called POL, the successor to MATIC under the same supply and the token every transaction on the network still pays fees in. If you bridge a stablecoin or ETH without also bringing a little POL, your new balance is visible but unusable until you acquire gas — either by bridging a small amount of POL alongside your main transfer or by swapping for it on a Polygon decentralized exchange right after you arrive. Fees on Polygon itself are small next to Ethereum, but a transaction with zero POL in the wallet still cannot be sent at all.

A deposit through the Polygon Bridge costs Ethereum gas for the lock transaction and nothing extra once it lands, since minting on Polygon is handled by the network's own validators. A withdrawal costs Polygon gas to burn the asset and then Ethereum gas again to claim it once the checkpoint containing that burn has been submitted. The table below lines up what each direction costs and roughly how long it takes.

Direction	What you pay	Typical time
Deposit to Polygon	Ethereum gas for the lock transaction	About 20–30 minutes
Activity on Polygon	POL gas, low cost	Seconds
Withdrawal to Ethereum	Polygon gas, then Ethereum gas to claim	Hours, until the next checkpoint

Checkpoints and the withdrawal delay

Checkpoints are submitted on a fixed interval rather than continuously, so a withdrawal you start a minute before one is submitted can finish far sooner than one started a minute after. There is no way to speed this up from your side; the practical move is to plan withdrawals for when you don't need the funds within the hour and to check PolygonScan for the current checkpoint status if the wait feels unusually long.

The sequence below is the same whether you're moving ETH, a stablecoin, or any other supported ERC-20 across the Polygon Bridge.

• Open the bridge interface and set Ethereum as the source network and Polygon as the destination.
• Pick the asset and amount; an ERC-20 usually needs a one-time approval before the deposit transaction.
• Sign the deposit transaction and pay Ethereum gas, then wait for the state sync to credit your Polygon address.
• Use the asset on Polygon — swap, lend, or hold it — paying transaction fees in POL.
• To bring it back, start a withdrawal on Polygon, wait for the checkpoint, then submit the claim transaction on Ethereum.

Why withdrawals need checkpoint confirmation

A withdrawal can't be claimed on Ethereum until the Polygon block that burned your asset is provably part of the chain Ethereum has accepted, and a checkpoint is exactly that proof. Skipping or shortening this wait would mean trusting an unconfirmed Polygon state, which defeats the point of anchoring the chain to Ethereum in the first place.

The canonical Polygon Bridge contracts are open, audited, and widely used, so the remaining risk sits mostly with the choices you make at the interface and at the signing prompt rather than with the bridge code itself.

Review contract addresses and approvals

Before approving an ERC-20 for the bridge, confirm the spender address matches the official deposit contract listed in Polygon's documentation, and check any past approvals you no longer need on PolygonScan's token approval checker. A mismatched address is the most common way users send funds to the wrong place.

What you control at the moment of signing

Every deposit and withdrawal is a transaction your wallet displays before you approve it, naming the contract, the asset, and the amount. Reading that screen rather than clicking through it is the actual safeguard a bridge offers; the Polygon Bridge cannot protect you from a transaction you approved without checking what it said.

The PoS chain isn't the only Polygon network reachable from Ethereum. Polygon zkEVM uses validity proofs instead of a checkpoint-and-challenge model, and its bridge contract verifies a cryptographic proof rather than waiting on a fixed submission schedule, a design tracked independently on L2BEAT alongside other proof-based rollups. Newer Polygon chains connect through AggLayer, a shared settlement layer designed to let assets move between Polygon chains without routing every hop back through Ethereum.

What AggLayer connects

AggLayer aggregates proofs from multiple Polygon chains so that a transfer between two of them can settle without a full Ethereum round trip on each side, aiming for the kind of unified liquidity described on ethereum.org's scaling overview for the layer-2 ecosystem generally. It's a newer piece of the stack than the PoS bridge, so check which chains a given AggLayer route actually supports before relying on it.

The canonical Polygon Bridge mints the official wrapped representation of your asset and is the reference path documented by the project itself, which the network's history on Wikipedia covers alongside Polygon's broader design. Third-party liquidity bridges can complete a withdrawal in minutes instead of hours because they front funds from their own pool rather than waiting on a checkpoint, but that speed comes with an extra fee and an extra party to trust. For a first transfer, or for any amount you'd rather not second-guess, the canonical route is the simpler choice; a faster third-party route is worth considering only once you've checked its reputation and the amount it actually quotes after fees.