---
title: "base_transactionStatus"
description: "Reports whether a transaction hash is present in the node mempool, useful for confirming submission before pre-confirmation lands."
source: https://basehub.org/api-reference/flashblocks/base_transactionstatus/
---
Reports whether a specific transaction is present in the node mempool. Use it to confirm that a submitted transaction has been received before it appears in a Flashblock.

Only available on Flashblocks endpoints: `https://mainnet-preconf.base.org` / `https://sepolia-preconf.base.org`.

Requires [base/base](https://github.com/base/base) minimum client version v0.3.0.

## Parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `transactionHash` | string | Yes | The 32-byte transaction hash to query. |

## Returns

`result` is the transaction status object:

| Field | Type | Description |
| --- | --- | --- |
| `status` | string | `"Known"` if the transaction is present in the mempool. `"Unknown"` if the node has not seen it. |

## Example

### Request

```bash
curl https://mainnet-preconf.base.org \
  -X POST -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"base_transactionStatus","params":["0xabc123..."],"id":1}'
```

### Response (Known)

```json
{"jsonrpc": "2.0", "id": 1, "result": {"status": "Known"}}
```

### Response (Unknown)

```json
{"jsonrpc": "2.0", "id": 1, "result": {"status": "Unknown"}}
```