eth_getTransactionByBlockHashAndIndex

eth_getTransactionByBlockHashAndIndex locates a block by its 32-byte hash and returns the single transaction sitting at the supplied zero-based index within that block. The transaction is returned as the standard Ethereum transaction object.

Use it when you already hold a block hash — from a log, a receipt, or an eth_getBlockByHash response — and want to walk that block's transactions one at a time without downloading the full block body. Pair it with eth_getBlockTransactionCountByHash: fetch the count, then iterate 0 … count-1, requesting each transaction by index.

If the block hash is unknown (e.g. an orphaned/uncle block, or a block the node has not yet seen) or the index is out of range for the block, the method returns null instead of an error. Always check for null before reading fields off the result.

Two positional parameters, in order.

When the block hash is unknown or the index is out of range, the result is null:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": null
}

A missing block or out-of-range index is not an error — it is reported as result: null (see above). A -32003 response carries Retry-After and X-RateLimit-Reset headers plus a data object with limit_rps, burst_capacity, and retry_after_sec. See errors.md for the full error envelope and handling guidance.

JavaScript (fetch)

const res = await fetch("https://api.triport.io/v1/ethereum", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.TRIPORT_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    jsonrpc: "2.0",
    id: 1,
    method: "eth_getTransactionByBlockHashAndIndex",
    params: [
      "0xb9b8b8b1b0c9e6a0f3d4c5b6a7988e9d0c1b2a3948576f5e4d3c2b1a09876543",
      "0x0",
    ],
  }),
});


const { result } = await res.json();
console.log(result === null ? "no transaction at that index" : result.hash);

TypeScript SDK (@triport/sdk)

import { Triport } from "@triport/sdk";


const client = new Triport({ apiKey: process.env.TRIPORT_API_KEY! });


const tx = await client.ethereum.request<Record<string, unknown> | null>(
  "eth_getTransactionByBlockHashAndIndex",
  [
    "0xb9b8b8b1b0c9e6a0f3d4c5b6a7988e9d0c1b2a3948576f5e4d3c2b1a09876543",
    "0x0",
  ],
);
console.log(tx === null ? "no transaction at that index" : tx.hash);

Python (triport-sdk)

import os
from triport import Triport


client = Triport(api_key=os.environ["TRIPORT_API_KEY"])


tx = client.ethereum.request(
    "eth_getTransactionByBlockHashAndIndex",
    [
        "0xb9b8b8b1b0c9e6a0f3d4c5b6a7988e9d0c1b2a3948576f5e4d3c2b1a09876543",
        "0x0",
    ],
)
print("no transaction at that index" if tx is None else tx["hash"])

• The index is a hex string (0x0, 0x1, …), not a decimal number.
• Always handle the null case: an unknown block hash or an out-of-range index returns result: null rather than an error.
• EIP-1559 fee fields (maxFeePerGas, maxPriorityFeePerGas) appear only on type 0x2 transactions; legacy transactions expose gasPrice only.
• Available on the free tier (eth_read_rpc category).
• Rate limiting is RPS-per-tier with burst; there is no daily quota. A -32003 rate_limited error means you should back off and retry shortly.
• To fetch the same transaction by block height instead of hash, use eth_getTransactionByBlockNumberAndIndex. To look a transaction up directly by its hash, use eth_getTransactionByHash. To learn how many transactions a block holds, use eth_getBlockTransactionCountByHash.