> ## Documentation Index
> Fetch the complete documentation index at: https://www.helius.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# sendBundle

> Submit an atomic bundle of up to 5 signed transactions via Jito's Block Engine. Proxied through your Helius RPC endpoint.

Submit a bundle of up to 5 fully-signed transactions for atomic execution. All transactions execute sequentially — if any fails, the entire bundle is rejected.

Requires a tip to a [Jito tip account](/sending-transactions/send-bundle#tip-accounts) in at least one transaction.

## Rate Limits

`sendBundle` is rate limited to **5 requests per second per project**. `getBundleStatuses` and `simulateBundle` use the general RPC rate limit.

<Tip>
  Need higher rate limits? [Contact our sales team](https://www.helius.dev/contact).
</Tip>

## Endpoint

```
POST https://mainnet.helius-rpc.com/?api-key=YOUR_API_KEY
```

## Request

<ParamField body="jsonrpc" type="string" required>
  `"2.0"`
</ParamField>

<ParamField body="id" type="number" required>
  Request identifier.
</ParamField>

<ParamField body="method" type="string" required>
  `"sendBundle"`
</ParamField>

<ParamField body="params[0]" type="array[string]" required>
  Array of up to 5 fully-signed transactions, base64 encoded.
</ParamField>

<ParamField body="params[1].encoding" type="string">
  `"base64"` (recommended) or `"base58"`. Default: `"base58"`.
</ParamField>

## Headers

<ParamField header="jito-region" type="string">
  Optional. Route to a specific Jito Block Engine region. Values: `ams`, `dub`, `fra`, `lon`, `nyc`, `slc`, `sgp`, `tyo`, `mainnet`. If omitted, routes to the global endpoint (geo-routed to nearest).
</ParamField>

## Request Example

```bash theme={"system"}
curl "https://mainnet.helius-rpc.com/?api-key=YOUR_API_KEY" \
  -X POST \
  -H "Content-Type: application/json" \
  -H "jito-region: nyc" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "sendBundle",
    "params": [
      [
        "BASE64_SIGNED_TX_1",
        "BASE64_SIGNED_TX_2"
      ],
      {
        "encoding": "base64"
      }
    ]
  }'
```

## Response

<ResponseField name="result" type="string">
  Bundle ID (SHA-256 hash of the transaction signatures). Use with `getBundleStatuses` to track landing.
</ResponseField>

```json theme={"system"}
{
  "jsonrpc": "2.0",
  "result": "892b79ed49138bfb3aa5441f0df6e06ef34f9ee8f3976c15b323605bae0cf51d",
  "id": 1
}
```

## See Also

* [Jito Bundles via Helius](/sending-transactions/send-bundle) — full guide with region routing, tip accounts, and requirements
* [getBundleStatuses](/api-reference/sender/getbundlestatuses) — check bundle landing status
* [simulateBundle](/api-reference/rpc/http/simulatebundle) — test bundles before submitting