MetaMask doesn't include Polygon out of the box by default, which is confusing for many new users considering that Polygon is one of the most popular Ethereum-compatible blockchains. In order to use Polygon - be it for lower fees, NFT marketplaces, or DeFi apps running on it - you should add the network to your wallet. Below are instructions on how to do this in two ways: quickly via one-click addition and manually by inputting the network RPC info.
What Is Polygon and Why Does It Require Additional Set Up in MetaMask?
Polygon is a separate blockchain platform working as a layer-2 solution for Ethereum and offering much lower fees and shorter transaction confirmation times. The protocol uses a proof-of-stake consensus algorithm and regularly checkpoints its current state to the Ethereum blockchain, thus partially relying on the security provided by Ethereum mainnet.
Since Polygon is a separate blockchain, MetaMask considers it a separate network with its own RPC endpoint, chain ID, and native currency. Your wallet supports any EVM-compatible blockchain in theory, but recognizes only those networks which you have added yourself, including Ethereum mainnet and several test networks.
What Is Required in Order to Add Polygon?
First of all, you will need to have a MetaMask wallet set up. The same wallet works with any EVM-compatible network and does not require the creation of a new wallet when connecting to Polygon.
Secondly, you will need to have a small amount of MATIC (Polygon's native token) in your wallet to cover transaction fees in the future. If your wallet doesn't have any MATIC in it yet, you can either bridge funds from Ethereum to Polygon (this topic will be covered in the next section) or purchase it from an exchange supporting Polygon withdrawals.
Method 1: Adding Polygon to MetaMask via One Click
The quickest way to add Polygon is via Chainlist, a community-built collection of EVM-based networks, or by clicking a button on the official Polygon website. Both options allow you to add the network to your MetaMask wallet in one click without entering any RPC info manually.
Adding Via Chainlist
Open the Chainlist website in your MetaMask-enabled browser and search for "Polygon" in the list of networks. The mainnet entry will probably be labeled "Polygon Mainnet" or just "Polygon." Press "Connect Wallet" and then press "Add to MetaMask" for the corresponding network entry. MetaMask will open a pop-up with the network name, RPC URL, chain ID, and currency symbol. Approve the information and press "Switch network" to use Polygon.
Adding via Polygon Website
The official Polygon website features a button labeled "Add Polygon Network" in the documentation and wallet setup sections. Tapping this button will launch the process described above via MetaMask.
Method 2: Adding Polygon to MetaMask Manually
For those who prefer to enter the info themselves or cannot use the one-click option for some reason, there is also a way to add the network manually in a few simple steps.
Step 1: Opening Network Settings
Open MetaMask and press the network selector at the top of the window. By default, it shows "Ethereum Mainnet." Now press "Add network" and then "Add a network manually."
Step 2: Entering Network Info
Enter the following fields exactly as shown below:
Network name: Polygon Mainnet
New RPC URL: https://polygon-rpc.com
Chain ID: 137
Currency symbol: MATIC
Block explorer URL: https://polygonscan.com
The Chain ID field requires special attention from you, as an error in it can lead to failed transactions or, even worse, a connection to a fraudulent network designed for phishing.
Step 3: Saving and Switching
Press "Save" once all fields are entered, and MetaMask will add Polygon to your networks. Press the network selector again and choose Polygon to set it as your active network. Your wallet address won't change, but your balance will be shown for Polygon from now on.
Verifying the Successful Connection to Polygon
First, you should make sure that the Chain ID is 137. Any other value in this field is a common indicator of phishing websites trying to get you to enter network info manually.
Also, you can verify if the connection is working correctly by checking your wallet balance on Polygonscan, the Polygon network block explorer. If the balance displayed on Polygonscan matches the one in MetaMask, everything is working fine.
Transferring Funds Onto Polygon
Adding the network only gives you the ability to use Polygon but doesn't send any funds onto it. Therefore, in order to make transactions on the network, you will need to have MATIC, or another token, deposited on Polygon. There are two common methods of transferring tokens:
Bridging from Ethereum Mainnet
The official Polygon Bridge allows you to transfer ETH or any ERC-20 tokens from Ethereum mainnet to Polygon. Connect your MetaMask to the bridge, choose the asset you want to transfer, and confirm the transaction on Ethereum. The transfer to Polygon usually occurs within several minutes after confirmation on the mainnet because moving assets onto Polygon is much faster than moving them back out.
Withdrawing Directly from the Exchange
Many centralized exchanges have the ability to withdraw MATIC and other tokens directly onto Polygon. All you have to do is choose Polygon as the withdrawal network on the exchange and provide your wallet address.
Transferring Funds Back from Polygon
In order to return funds from Polygon to Ethereum mainnet via the official bridge, you will need to wait much longer than for depositing them onto the network, generally due to checkpoint timing -- Polygon periodically submits proofs of its state to Ethereum, and withdrawals need to wait for the relevant checkpoint to be confirmed. The average time required for the completion of a withdrawal is usually around three hours, although it varies.
However, there are some third-party bridges that offer much faster transfers by providing the funds to cover the withdrawal in advance and charging an extra fee for the operation.
Common Problems With Polygon
In case your balance is zero after switching to Polygon, it is probably because you haven't moved the funds from the mainnet yet. Check your balance on Polygon by looking up your address on Polygonscan.
If your RPC URL does not work, it might be because of an overloaded public endpoint. Such cases happen sometimes with free public endpoints during periods of high network activity. In order to fix the problem, you will have to switch to another public RPC URL (several of them are listed on Chainlist), or use a private node provider.
If the token that you received on Polygon doesn't appear in your wallet, you will have to add it manually. Just switch to the Polygon network, go to the "Assets" tab, press "Import tokens," and enter the token's contract address on Polygon.
MATIC, POL, and Gas Fees on Polygon
Gas fees on Polygon are paid in MATIC (the network's native token) and are significantly lower than the fees for the same transaction on Ethereum mainnet. Lower gas fees are one of the reasons why developers and users decide to build and use dApps on Polygon.
The project has also launched a token called POL intended to replace MATIC as the main gas token across Polygon's ecosystem of chains. Depending on when you read this, MATIC may still be used as the gas token on Polygon mainnet. However, the transition is still ongoing -- check Polygon's documentation in order to find the current information on this matter.
Conclusion
Adding Polygon to MetaMask is a one-time process, whether performed via a one-click website or manually by entering RPC info. You should pay the most attention to the chain ID (137) and the correct RPC endpoint while setting up the network, as any mistake in these parameters is likely to result in failed transactions or even exposure to phishing.
Once the network is successfully added and funds are transferred to it, using Polygon will be just the same as using any other EVM-compatible blockchain, except for the lower fees.
FAQ
Q: What is the chain ID for Polygon? A: The chain ID for Polygon is 137. This parameter is used by MetaMask and other wallets in order to recognize the proper target network of the transaction or the connection.
Q: Do I need a new wallet to use Polygon? A: No. Since Polygon is EVM-compatible, your address will be able to operate on this network without any changes. All you need to do is add the network to your wallet.
Q: Why does my balance show zero on Polygon? A: A zero balance after changing the network is probably due to the fact that you haven't moved the funds to Polygon yet. Each network connected to MetaMask has its own balance, and you can't see funds from Ethereum on Polygon by default.
Q: How long does bridging to Polygon take? A: Bridging to Polygon is quite fast and usually finishes within several minutes after confirmation on Ethereum.
Q: Why does withdrawing from Polygon take longer? A: In order to withdraw funds from Polygon using the official bridge, you have to wait until the network checkpoint occurs - the periodic proof Polygon submits to Ethereum confirming its state. It is a common process which takes a few hours, although you can try some third-party bridges offering faster transfers for a fee.
Q: Is MATIC the same as POL? A: POL is a newer token intended to replace MATIC as the gas and staking token in the Polygon ecosystem. However, depending on the current upgrade status of the network, MATIC may still be the active gas token. So, you should check Polygon's official documentation in order to know the current situation.
Q: Can I add Polygon without using Chainlist? A: Yes. You can add it manually by entering the RPC info, chain ID, currency symbol, and block explorer URL into the "Add a network manually" form in MetaMask.
Q: Why is my token not showing up after receiving it on Polygon? A: Sometimes MetaMask does not detect new tokens automatically. In this case, you can add the token manually by using the "Import tokens" button in the "Assets" tab and the contract address of the token on the Polygon network.
Q: What currency is used for the payment of gas fees on Polygon? A: On Polygon, gas fees are paid in MATIC, the network's native token. Usually, the fees on this network are significantly lower than on Ethereum.
Q: How can I tell if an "Add Polygon" prompt is legitimate? A: Make sure that the chain ID of the network is 137 and the RPC URL is legitimate. Any other chain ID or an unknown RPC address may indicate that the website is trying to scam you.