WETH source representation
WETH is classified as a wrapped asset for this route. WETH uses a wrapped contract asset on Polygon. The recorded Polygon representation uses 18 decimal places. WETH leaves through a wrapper contract and needs native chain gas. A WETH token balance cannot pay the gas required to submit its own transfer.
EVM-to-EVM execution boundary
Polygon and Ethereum can use the same 0x address syntax, but they are separate networks with different chain identifiers, gas balances, token contracts, and transaction histories.
WETH destination representation
WETH is classified as a wrapped asset for this route. WETH uses a wrapped contract asset on Ethereum. The recorded Ethereum representation uses 18 decimal places. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
Ethereum receipt-side execution
Ethereum is a L1 EVM network in the Ethereum ecosystem. ETH pays destination-side network gas on Ethereum. EVM 0x account address An Ethereum receipt is an L1 native ETH balance or ERC-20 contract event; later token movement can require ETH gas and a new approval for another contract.
Polygon deposit-side execution
Polygon is a L1 EVM network in the Polygon ecosystem. POL pays source-side network gas on Polygon. EVM 0x account address A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1.
WETH unwrap or exchange input check
WETH is a contract wrapper for ETH. It can be transferred as a token but cannot replace the native gas balance required by the network. On this route WETH is the source token on Polygon. Its token balance, approvals, and contract transfer behavior are separate from the native coin used for network gas.
Polygon to Ethereum bridge mistakes
Route-specific mistakes include sending on a network other than Polygon; using a destination that is not valid for Ethereum; running out of POL before the source transaction is submitted; treating a wrapped token as the native gas asset. A Polygon PoS source uses its validator/checkpoint system and POL gas; its token contracts and checkpoints are separate from Ethereum L1. WETH leaves through a wrapper contract and needs native chain gas. A WETH token balance cannot pay the gas required to submit its own transfer. An Ethereum receipt is an L1 native ETH balance or ERC-20 contract event; later token movement can require ETH gas and a new approval for another contract. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.