How to bridge tokens from Ethereum to Polygon

There are tons of layer-1 and layer-2 networks to build projects on, and each one offers different benefits and drawbacks. Spritz supportsPolygon network to let you send bill payments directly to your accounts with your preferred crypto wallet. Polygon offers fast transaction speeds and low gas fees, making it a great choice for payments with crypto, plus it's easy to bridge assets from other networks to Polygon to save on gas fees! 

Why do I need to use a Polygon bridge?

The Ethereum blockchain is by far the most popular layer-1 blockchain in use today. Its robust ecosystem and wide global user base makes it a popular network for things like NFTs and decentralized metaverse platforms like Decentraland. Ethereum was the first decentralized blockchain to introduce smart contracts, bringing a world of new use cases to blockchain technology that is not possible on networks like Bitcoin. However, it does come with its own drawbacks.

For one, Ethereum is slow. As the first smart contract-capable blockchain it enabled developers to create projects on top of the network, but the network itself is slow and expensive to use because it uses a Proof-of-Work mechanism. Enter the Polygon sidechain, a layer-2 scaling solution for Ethereum that allows developers to deploy smart contracts—and for individuals to use the network, at a much faster and more affordable rate.

Gas fees on Ethereum are expensive, and transactions can take several minutes to several hours to confirm on the network depending on how congested it is at any given time. If Spritz were to launch on the Ethereum mainnet, you could spend a lot of money on gas fees and have to wait a long time for your bills to get paid.

The Polygon Bridge enables the fast transfer of assets like crypto from the Ethereum blockchain onto the Polygon network. This lets you easily send your crypto from one network to another in just a couple of seconds, so that you can then pay your bills quickly and in only a few pennies worth of crypto in gas fees.

How do I use the Polygon bridge?

We’re glad you asked! It’s very easy, but we can understand if you’re nervous about whether you’ll do it right the first time. The first thing you’ll need to do is open a Polygon wallet through your preferred crypto wallet. Spritz accepts most major wallets, including MetaMask and Coinbase Wallet.

On MetaMask:

Open your wallet within your browser and click on the drop down menu at the top that says “Ethereum Mainnet,” click on “Add Network” and search for the Polygon Mainnet. You can also add the Chain ID for Polygon: 137

On Coinbase Wallet:

Within your mobile Coinbase wallet click on “Settings,” then click on “Active Network” and then “Polygon Mainnet” from the list of options. If the Polygon Mainnet isn’t available, try updating your app. You’ll need to go back to the Ethereum Mainnet in order to bridge your assets, but this will teach you how to access your Polygon assets once they’re bridged.

After you’ve added the network to your wallet, switch back to your Ethereum wallet and head to https://wallet.polygon.technology/login/ to access your Polygon wallet and the Polygon PoS bridge. Use your preferred crypto wallet to connect to the website and confirm your login within your wallet of choice. You should never be asked for your private keys.

Click on the bridge icon to be redirected to the Polygon PoS bridge, and follow the prompts to bridge whichever Ethereum assets you want to the Polygon network. Once you sign the transaction in your wallet and approve the gas fees, it should only take a couple of minutes for the assets to bridge.

Are there any risks involved by using the Polygon bridge?

There are. To properly explain the risks you’ll need to understand how a bridge works. Most bridging protocols let users bridge their assets by swapping them from the native token to a token that can represent it on another network—like swapping Bitcoin for Wrapped Bitcoin, ETH to WETH, and so on. When you bridge those assets you’re essentially dropping off your tokens into a pool of assets that then issue the representative token on the other network.

Think of it like an arcade. You go to the arcade with a roll of quarters but realize when you get there that the arcade has its own coins, so you go to the machine that lets you buy tokens with your quarters. The machine is both the bridge, letting you swap your assets, and the liquidity pool holding both types of assets. If someone were to steal all of the quarters or arcade tokens in the machine, its swapping mechanism wouldn’t work.

A blockchain bridge is similar, but the risk comes from the network being attacked and not necessarily the bridge itself, though that can happen. Since the assets you’ve bridged are all sitting in one pool, they’re susceptible to attacks that make them vulnerable. We recommend picking a bridge that is reputable and has a long history of operating without being attacked. You can minimize risk by picking well known and widely used bridging protocols with a good security mechanism.

Projects that are more decentralized or are widely used and distributed across a lot of nodes as opposed to just a few are safer as well, since an attacker would have to take over more nodes in order to break into the network. Bridges like the Polygon PoS are widely used and distributed across a network of validators.

Not all bridges are built the same, so you’ll want to find one that can transfer assets quickly while also checking off all of the security requirements you have. Some Sprites love using bridges like Hop and Across, which are great options for both security and affordability, as well as speed. Both Hop and Across are great options if you have tokens on other Ethereum layer-2 scaling chains, such as Arbitrum and Optimism, and looking to bridge assets from those networks to Polygon.

The Arbitrum Bridge is also popular, though the transaction may take a couple of days. We personally love the Polygon PoS bridge, which works with assets on Ethereum..

Bridging assets from other networks onto Polygon is quick and easy, just like Spritz.  Once you bridge your assets you can quickly pay your bills, off-ramp, or load your SpritzCard with lower gas fees than other networks. Just head to your Spritz account, answer a few questions to connect your bills and set up your payment. The whole thing will only take a couple of minutes, that way you can spend your time doing something more fun. Cheers!