eth_createAccessList - Monad

Example code for the eth_createAccessList JSON-RPC method. Complete guide on how to use eth_createAccessList JSON-RPC in GetBlock Web3 documentation.

This method creates an EIP-2930 access list that describes all storage slots and addresses accessed during a transaction simulation.

Parameters

Parameter	Type	Required	Description
transaction	object	Yes	The transaction call object.
transaction.from	string	No	The address the transaction is sent from.
transaction.to	string	Yes	The address the transaction is directed to.
transaction.gas	string	No	Gas provided for the call (hex).
transaction.gasPrice	string	No	Gas price in wei (hex).
transaction.value	string	No	Value sent with the call (hex).
transaction.data	string	No	Hash of the method signature and encoded parameters.
blockNumber	string	No	Block number in hex, or "latest", "earliest", "pending".

Request

cURL

curl

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_createAccessList",
    "params": [{
        "from": "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb",
        "to": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
        "data": "0xa9059cbb000000000000000000000000..."
    }, "latest"],
    "id": "getblock.io"
}'

Axios

Request

Rust

Response

response.json

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": {
        "accessList": [
            {
                "address": "0xdac17f958d2ee523a2206206994597c13d831ec7",
                "storageKeys": [
                    "0x0000000000000000000000000000000000000000000000000000000000000000",
                    "0x0000000000000000000000000000000000000000000000000000000000000001"
                ]
            }
        ],
        "gasUsed": "0x5208"
    }
}

Response Parameters

Field	Type	Description
accessList	array	Array of addresses and storage keys accessed.
accessList[].address	string	Contract address accessed.
accessList[].storageKeys	array	Array of storage slots accessed in that contract.
gasUsed	string	Estimated gas with the access list.

Use Case

The eth_createAccessList method is essential for:

• Gas optimization with EIP-2930 transactions

• Pre-warming storage slots

• Transaction simulation analysis

• Gas cost reduction strategies

• DeFi transaction optimization

• Understanding contract interactions

Error Handling

Status Code	Error Message	Cause
403	Forbidden	Missing or invalid ACCESS-TOKEN.
-32602	Invalid params	Invalid transaction parameters.
-32000	Execution reverted	Transaction would revert.

Web3 Integration

Ethers.js

ethers-createAccessList.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider('https://go.getblock.io/<ACCESS-TOKEN>/');

const tx = {
    from: senderAddress,
    to: contractAddress,
    data: encodedFunctionData
};

const result = await provider.send('eth_createAccessList', [tx, 'latest']);

console.log('Access list:', result.accessList);
console.log('Gas with access list:', parseInt(result.gasUsed, 16));

// Use in transaction
const txWithAccessList = {
    ...tx,
    type: 1, // EIP-2930 transaction
    accessList: result.accessList
};