Sign a Transaction

Sign an EVM transaction without broadcasting it to the network.

Use signTransaction on a Viem WalletClient to produce a signed, serialized transaction without submitting it. This is useful when you need to:

• Hand the signed transaction to a relayer or sponsor service for submission.
• Co-sign a multi-step flow before broadcasting atomically.
• Inspect or store the raw signed bytes before sending.

Usage

JavaScript

import { parseEther } from 'viem';
import { createWalletClientForWalletAccount } from '@dynamic-labs-sdk/evm/viem';

const signTransaction = async (walletAccount) => {
  const walletClient = await createWalletClientForWalletAccount({ walletAccount });

  const signedTx = await walletClient.signTransaction({
    to: '0x0000000000000000000000000000000000000000',
    value: parseEther('0.05'),
  });

  console.log('signed transaction:', signedTx);
  return signedTx;
};

React

import { parseEther } from 'viem';
import { createWalletClientForWalletAccount } from '@dynamic-labs-sdk/evm/viem';
import { isEvmWalletAccount } from '@dynamic-labs-sdk/evm';
import { useWalletAccounts } from '@dynamic-labs-sdk/react-hooks';

function SignTransactionButton() {
  const walletAccounts = useWalletAccounts();
  const walletAccount = walletAccounts.find(isEvmWalletAccount);

  const handleSign = async () => {
    if (!walletAccount) return;

    const walletClient = await createWalletClientForWalletAccount({ walletAccount });

    const signedTx = await walletClient.signTransaction({
      to: '0x0000000000000000000000000000000000000000',
      value: parseEther('0.05'),
    });

    console.log('signed transaction:', signedTx);
  };

  return (
    <button onClick={handleSign} disabled={!walletAccount}>
      Sign transaction
    </button>
  );
}

Submitting later

The output of signTransaction is a serialized, signed transaction (hex). When you’re ready to broadcast it, send it through any RPC — for example, with a Viem PublicClient:

import { createPublicClientFromNetworkData } from '@dynamic-labs-sdk/evm/viem';
import { getActiveNetworkData } from '@dynamic-labs-sdk/client';

const { networkData } = await getActiveNetworkData({ walletAccount });
const publicClient = createPublicClientFromNetworkData({ networkData });

const txHash = await publicClient.sendRawTransaction({
  serializedTransaction: signedTx,
});

Notes

• The wallet account must be an EVM account. Narrow the type with isEvmWalletAccount before calling createWalletClientForWalletAccount.
• Some wallet apps refuse to sign without broadcasting — they will surface a user-rejection error in that case. Check the wallet’s UX expectations before relying on this flow in production.
• Signing uses the wallet’s currently active chain. Switch first with switchActiveNetwork if you need a different one.
• Need to estimate fees before signing? See Calculate EVM transaction fee.

Related functions

• Getting a Viem WalletClient
• Getting a Viem PublicClient
• Sign Typed Data (EIP-712)
• Simulate EVM transaction
• Calculate EVM transaction fee