How to Batch Multiple ETH Transfers in One Transaction Using Solidity and OpenZeppelin

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Sending Ether (ETH) to multiple addresses individually can be costly and inefficient due to high gas fees on Ethereum and other EVM-compatible blockchains. However, with smart contract automation, developers can optimize this process by batching multiple ETH transfers into a single transaction. This approach not only reduces gas costs but also improves transaction efficiency—especially useful for airdrops, payroll distributions, or reward systems.

In this guide, we’ll walk through how to implement batch ETH transfers using Solidity and the OpenZeppelin Address library, enabling you to send funds to multiple recipients in one go.

Understanding the Need for Batch Transfers

Every Ethereum transaction incurs gas fees. When sending ETH to 10 different addresses individually, you're executing 10 separate transactions—each with its own base cost. By batching these transfers into a single function call, you pay only one transaction fee plus minimal additional computation costs.

This technique is particularly valuable for:

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Core Tools: Solidity and OpenZeppelin

To build an efficient batch transfer system, we use:

The Address library from OpenZeppelin provides utilities like isContract() and helps safely convert addresses to payable types—critical when dealing with ETH transfers.

Key Keywords

These keywords reflect user search intent around cost-effective, scalable Ethereum transactions.

Step-by-Step Implementation

Let’s break down how to write a smart contract that enables batch ETH transfers.

1. Set Up the Contract Environment

Start by defining the Solidity version and importing the OpenZeppelin Address library:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/Address.sol";

Using SPDX ensures license transparency, while ^0.8.0 avoids known overflow vulnerabilities.

2. Use the Address Library

Leverage using Address for address payable; to extend functionality on address types:

using Address for address payable;

This allows safe operations such as checking if an address is a contract or sending ETH with error handling.

3. Create the Batch Transfer Function

Define a function that accepts two arrays: recipient addresses and corresponding ETH amounts (in Wei):

function batchTransferETH(address payable[] memory recipients, uint256[] memory amounts) external payable {
    require(recipients.length == amounts.length, "Arrays must be same length");

    uint256 totalAmount = 0;
    for (uint256 i = 0; i < recipients.length; i++) {
        totalAmount += amounts[i];
        recipients[i].transfer(amounts[i]);
    }
    require(msg.value >= totalAmount, "Insufficient ETH sent");
}
⚠️ Note: The function is payable because it receives ETH from the caller.

Each recipient must be of type address payable, so ensure frontend logic or helper functions handle string-to-address conversion securely.

4. Add a Receive Function

To accept plain ETH without data, include:

receive() external payable {}

This enables the contract to receive funds during deployment or direct transfers.

Deployment and Execution Tips

When deploying this contract:

  1. Choose a low-fee network: Consider using Polygon, Arbitrum, or Base for lower gas costs during testing and production.
  2. Fund the contract appropriately: Before calling batchTransferETH, send enough ETH to cover all payouts.
  3. Pass values in Wei: For example, 1 ETH = 1000000000000000000 Wei.

After deployment, calling the function with two arrays—one of addresses, one of amounts—executes all transfers within a single block, visible under one transaction hash.

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Frequently Asked Questions (FAQ)

Q: Why use OpenZeppelin’s Address library instead of direct transfers?

A: The Address library adds safety checks, especially important when interacting with contracts that may not handle incoming ETH correctly. It prevents reentrancy risks and ensures robust error handling during transfers.

Q: Can I send ETH to non-payable addresses using this method?

A: No. Only payable addresses can receive ETH via .transfer() or .send(). If you attempt to send to a non-payable address, the transaction will revert. Always validate addresses before inclusion.

Q: Is this method compatible with ERC-20 tokens?

A: Not directly. This contract handles native ETH only. For ERC-20 tokens, you’d need to use the token’s transfer or transferFrom functions with proper approvals.

Q: How much gas do I save with batch transfers?

A: While exact savings depend on network conditions, batching typically reduces per-transfer costs by 30–60%. Instead of paying ~21,000 gas per transfer, you pay once for the transaction plus ~1,000–5,000 extra per recipient.

Q: What happens if one transfer fails?

A: Since Solidity uses atomic execution, if any single transfer fails (e.g., due to out-of-gas or invalid address), the entire transaction reverts. This ensures consistency but requires careful input validation.

Q: Can I limit who can call the batch function?

A: Yes. Add access control using modifiers like onlyOwner or role-based permissions via OpenZeppelin’s AccessControl contract to restrict execution rights.

Real-World Use Cases

Such implementations streamline operations and reduce operational overhead significantly.

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Final Thoughts

Batching multiple ETH transfers in a single transaction is a powerful technique for improving scalability and reducing costs in blockchain applications. By leveraging Solidity’s flexibility and OpenZeppelin’s secure libraries, developers can create robust systems that serve real-world needs—from mass payments to automated disbursements.

As Ethereum Layer 2 solutions grow, optimizing gas usage becomes even more crucial. Implementing efficient patterns like batch transfers today prepares your dApp for tomorrow’s scale.

Whether you're building on Ethereum, Polygon, or another EVM chain, integrating gas-saving strategies enhances both user experience and economic viability.

Remember to test thoroughly on testnets like Sepolia or Mumbai before deploying to mainnet. With careful planning and secure coding practices, batch ETH transfers become a cornerstone of efficient blockchain development.