Skip to main content

Add a network

In some cases, such as when interacting with smart contracts, your dapp must connect a user to a new network in MetaMask. Instead of the user adding a new network manually, which requires them to configure RPC URLs and chain IDs, your dapp can use the wallet_addEthereumChain and wallet_switchEthereumChain RPC methods to prompt the user to add a specific, pre-configured network to their MetaMask wallet.

These methods are specified by EIP-3085 and EIP-3326, and we recommend using them together.

  1. wallet_addEthereumChain creates a confirmation asking the user to add the specified network to MetaMask.
  2. wallet_switchEthereumChain creates a confirmation asking the user to switch to the specified network.

The confirmations look like the following:

Add network confirmation
Switch network confirmation

Example

The following is an example of using wallet_addEthereumChain and wallet_switchEthereumChain to prompt a user to add and switch to a new network:

try {
await ethereum.request({
method: "wallet_switchEthereumChain",
params: [{ chainId: "0xf00" }],
});
} catch (switchError) {
// This error code indicates that the chain has not been added to MetaMask.
if (switchError.code === 4902) {
try {
await ethereum.request({
method: "wallet_addEthereumChain",
params: [
{
chainId: "0xf00",
chainName: "...",
rpcUrls: ["https://..."] /* ... */,
},
],
});
} catch (addError) {
// handle "add" error
}
}
// handle other "switch" errors
}