eth_createAccessList on Base

Measured 2026-10-04 by our weekly probe, which calls eth_createAccessList through the same Base endpoint customers use.

What eth_createAccessList does

Simulates a transaction and returns the EIP-2930 access list of addresses and storage keys it touches, plus the gas it would use with that list attached.

eth_createAccessList on Base: what we measured

• Default Base routing keeps state for roughly the last 1,000,000 blocks (about 23.1 days of Base history). Simulating against a block older than that needs historical state. Add &archive=1 to send the request to archive upstreams (paid plans).

Example request

curl -s https://rpc.swiftnodes.io/rpc/base?key=YOUR_API_KEY \
  -X POST -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"eth_createAccessList","params":[{"from":"0x0000000000000000000000000000000000000000","to":"0x0000000000000000000000000000000000000000","data":"0x"},"latest"]}'

import { createPublicClient, http } from "viem";

const client = createPublicClient({ transport: http("https://rpc.swiftnodes.io/rpc/base?key=YOUR_API_KEY") });

// Any JSON-RPC method, typed loosely: eth_createAccessList on Base
const result = await client.request({
  method: "eth_createAccessList",
  params: [{"from":"0x0000000000000000000000000000000000000000","to":"0x0000000000000000000000000000000000000000","data":"0x"},"latest"],
});

Other methods on Base

• eth_getLogsSupported
• eth_getBlockReceiptsSupported
• eth_feeHistorySupported
• eth_getProofSupported
• debug_traceCallSupported
• trace_blockSupported
• trace_transactionSupported

eth_createAccessList on other chains

Support differs by chain; the full measured table is on the eth_createAccessList reference.

• Ethereum
• Arbitrum
• Optimism
• Polygon
• BNB Smart Chain
• Avalanche
• Sonic
• Linea
• Scroll
• zkSync Era
• Blast
• Mantle
• Gnosis
• Celo
• Berachain
• Monad
• Unichain
• Kaia
• PulseChain

Frequently asked questions