Quick take: The Polygon PoS Bridge finalises withdrawals in ≈ 2-3 hours, while the Plasma Bridge uses a 7-day fraud-proof window for extra security.
Table of Contents
- Why Bridge from Ethereum to Polygon?
- PoS vs Plasma: Which Bridge Should You Use?
- Step-by-Step: Bridging ETH & ERC-20s (PoS)
- Bridging NFTs (ERC-721 & ERC-1155)
- Programmatic NFT Bridging with
matic-js - Fees & Gas-Saving Tips
- FAQs
- Final Thoughts
1. Why Bridge from Ethereum to Polygon?
- Lower fees: Polygon txs are typically < $0.01 vs several dollars on Ethereum.
- Faster UX: Deposits settle in minutes; PoS exits clear in ≈ 2-3 h.
- Ecosystem access: Trade NFTs gas-free, farm yield on Aave, dive into GameFi.
- Security inheritance: Assets remain locked by smart contracts on Ethereum.
Need a deep dive? Check our original Polygon Bridge Guide.
2. PoS vs Plasma: Which Bridge Should You Use?
| Feature | PoS Bridge | Plasma Bridge |
|---|---|---|
| Security model | Polygon validator set | Ethereum Plasma fraud proofs |
| Deposit time | ≈ 10-30 min | ≈ 10-30 min |
| Withdrawal time | ≈ 2-3 h | 7 days |
| Token support | Most ERC-20, 721, 1155 | ETH, MATIC, select ERC-20 |
| Best for | Everyday transfers, NFTs, DeFi | High-value, security-critical moves |
3. Step-by-Step: Bridging ETH & ERC-20s (PoS)
- Open Polygon Portal and connect MetaMask.
- Select Deposit, choose your token and amount.
- Click Transfer → Continue; approve the tx in MetaMask (pay ETH gas).
- Wait ≈ 10-30 min for the checkpoint—assets appear under “Polygon”.
- To withdraw, use Withdraw, start the exit, then return ~3 h later to claim on Ethereum.
Gas-saving tip: Bridge during off-peak hours when base fee < 20 gwei.
4. Bridging NFTs (ERC-721 & ERC-1155)
The PoS Bridge locks your NFT on Ethereum and mints a 1-to-1 copy on Polygon.
Wallet Method
- Select ERC-721 or ERC-1155 in the asset list.
- Approve the collection, confirm the transfer.
- Your NFT appears on OpenSea’s Polygon tab once the checkpoint finalises.
5. Programmatic NFT Bridging with matic-js
Automate transfers in your dApp:
// Initialise ERC-721 helpers
const erc721token = posClient.erc721(<tokenAddress>, <isRoot?>);
// Child token on Polygon
const childERC721 = posClient.erc721(<childTokenAddress>);
// Parent token on Ethereum (root)
const parentERC721 = posClient.erc721(<parentTokenAddress>, true);
6. Fees & Gas-Saving Tips
- Bridge fee: None—only network gas.
- ETH-side gas: Main cost; bridge when network is quiet.
- Polygon gas: Fractions of a cent—keep 0.1 MATIC (or POL) for exits.
- Batch NFTs: Use
depositMany/withdrawStartManyto save gas.
FAQs
PoS Bridge: 45 min–3 h. Plasma Bridge: up to 7 days.
Yes—USDC, DAI, USDT and other major stablecoins are whitelisted in the Polygon Portal.
zk-based exits can finalise in as little as 15 min, but NFT support and dApp compatibility are still expanding.
The contract will reject the transaction. Always verify token addresses before bridging.
8. Final Thoughts
Bridging between Ethereum and Polygon unlocks cheaper, faster, and richer Web3 experiences without leaving Ethereum’s security umbrella. Use the PoS Bridge for everyday transfers, switch to Plasma for high-value moves, and tap matic-js for code-level control. Dive deeper via our comprehensive guide and start saving on gas today.
Updated June 30 2025.
