eth_createAccessList

curl --request POST \
  --url https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14 \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "method": "eth_createAccessList",
  "id": 1,
  "params": [
    {
      "from": "0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63",
      "data": "0x608060806080608155"
    },
    "pending"
  ]
}
'

import requests

url = "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14"

payload = {
    "jsonrpc": "2.0",
    "method": "eth_createAccessList",
    "id": 1,
    "params": [
        {
            "from": "0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63",
            "data": "0x608060806080608155"
        },
        "pending"
    ]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    jsonrpc: '2.0',
    method: 'eth_createAccessList',
    id: 1,
    params: [
      {
        from: '0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63',
        data: '0x608060806080608155'
      },
      'pending'
    ]
  })
};

fetch('https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'jsonrpc' => '2.0',
    'method' => 'eth_createAccessList',
    'id' => 1,
    'params' => [
        [
                'from' => '0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63',
                'data' => '0x608060806080608155'
        ],
        'pending'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "jsonrpc": "<string>",
  "id": 123,
  "result": {
    "accessList": [
      {
        "address": "<string>",
        "storageKeys": [
          "<string>"
        ]
      }
    ],
    "gasUsed": "<string>"
  }
}

POST

2fc1de7f08c0465f6a28e3c355e0cb14

eth_createAccessList

curl --request POST \
  --url https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14 \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "method": "eth_createAccessList",
  "id": 1,
  "params": [
    {
      "from": "0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63",
      "data": "0x608060806080608155"
    },
    "pending"
  ]
}
'

import requests

url = "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14"

payload = {
    "jsonrpc": "2.0",
    "method": "eth_createAccessList",
    "id": 1,
    "params": [
        {
            "from": "0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63",
            "data": "0x608060806080608155"
        },
        "pending"
    ]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    jsonrpc: '2.0',
    method: 'eth_createAccessList',
    id: 1,
    params: [
      {
        from: '0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63',
        data: '0x608060806080608155'
      },
      'pending'
    ]
  })
};

fetch('https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'jsonrpc' => '2.0',
    'method' => 'eth_createAccessList',
    'id' => 1,
    'params' => [
        [
                'from' => '0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63',
                'data' => '0x608060806080608155'
        ],
        'pending'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://base-mainnet.core.chainstack.com/2fc1de7f08c0465f6a28e3c355e0cb14")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_createAccessList\",\n  \"id\": 1,\n  \"params\": [\n    {\n      \"from\": \"0xaeA8F8f781326bfE6A7683C2BD48Dd6AA4d3Ba63\",\n      \"data\": \"0x608060806080608155\"\n    },\n    \"pending\"\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "jsonrpc": "<string>",
  "id": 123,
  "result": {
    "accessList": [
      {
        "address": "<string>",
        "storageKeys": [
          "<string>"
        ]
      }
    ],
    "gasUsed": "<string>"
  }
}

Base API method eth_createAccessList generates an access list for a transaction based on specific default values. An access list includes addresses and storage keys the transaction intends to access, facilitating more efficient gas usage.

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Parameters

transactionObject — an object containing transaction parameters with default values:
- from — the address of the sender.
- data — the data being sent with the transaction.
blockParameter — specifies the blockchain state to use for generating the access list, with a default value of "pending".

Response

result — an object containing:
- accessList — the generated access list, detailing addresses and storage keys the transaction will access.
- gasUsed — the estimated gas used to execute the transaction with the generated access list.

Use case

The eth_createAccessList method is crucial for:

Preparing transactions that optimize gas usage by explicitly stating which addresses and storage keys will be accessed.
Developers aiming to reduce transaction costs and improve efficiency on the Base network.
Transactions that comply with EIP-2930, which introduces access lists as a transaction type to specify state access.

This method provides a practical approach to optimizing transaction execution and gas usage on the Base blockchain by pre-determining the access list.

Body

application/json

jsonrpc

string

default:2.0

method

string

default:eth_createAccessList

integer

default:1

params

(object | string)[]

Show child attributes

Response

200 - application/json

The generated access list and gas used

jsonrpc

string

integer

result

object

Show child attributes

Last modified on June 22, 2026

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Chainstack platform API

eth_createAccessList | Base

Parameters

Response

Use case

Body

Response

​Parameters

​Response

​Use case

Body

Response

Parameters

Response

Use case