Ethers.js: How to send EIP-1559 transactions

Ethers is pretty cool and is able to send a eip-1559 transaction automatically without a need to do any extra configuration. It will use a maxPriorityFeePerGas of 1.5 Gwei by default, starting with v5.6.0. Also, if you use a signer class that would know also how to manage the nonce for you (of course that if you want to always get the mined transactions count). Here’s a simple script that would send such a transaction:

const { ethers } = require("ethers");

async function main() {
  // Configuring the connection to an Ethereum node
  const network = process.env.ETHEREUM_NETWORK;
  const provider = new ethers.providers.InfuraProvider(
    network,
    process.env.INFURA_PROJECT_ID,
  );
  // Creating a signing account from a private key
  const signer = new ethers.Wallet(process.env.SIGNER_PRIVATE_KEY, provider);

  // Creating and sending the transaction object
  const tx = await signer.sendTransaction({
    to: "<to_address_goes_here>",
    value: ethers.utils.parseUnits("0.001", "ether"),
  });
  console.log("Mining transaction...");
  console.log(`https://${network}.etherscan.io/tx/${tx.hash}`);
  // Waiting for the transaction to be mined
  const receipt = await tx.wait();
  // The transaction is now on chain!
  console.log(`Mined in block ${receipt.blockNumber}`);
}

require("dotenv").config();
main();

However, if you want to manually control the tx object parameters here’s how the above script changes:

const { ethers } = require("ethers");

async function main() {
  // Configuring the connection to an Ethereum node
  const network = process.env.ETHEREUM_NETWORK;
  const provider = new ethers.providers.InfuraProvider(
    network,
    process.env.INFURA_PROJECT_ID,
  );
  // Creating a signing account from a private key
  const signer = new ethers.Wallet(process.env.SIGNER_PRIVATE_KEY, provider);

  const limit = provider.estimateGas({
    from: signer.address,
    to: "<to_address_goes_here>",
    value: ethers.utils.parseUnits("0.001", "ether"),
  });

  // Creating and sending the transaction object
  const tx = await signer.sendTransaction({
    to: "<to_address_goes_here>",
    value: ethers.utils.parseUnits("0.001", "ether"),
    gasLimit: limit,
    nonce: signer.getTransactionCount(),
    maxPriorityFeePerGas: ethers.utils.parseUnits("2", "gwei"),
    chainId: 3,
  });
  console.log("Mining transaction...");
  console.log(`https://${network}.etherscan.io/tx/${tx.hash}`);
  // Waiting for the transaction to be mined
  const receipt = await tx.wait();
  // The transaction is now on chain!
  console.log(`Mined in block ${receipt.blockNumber}`);
}

require("dotenv").config();
main();