# pimlico\_sendUserOperationNow

`pimlico_sendUserOperationNow` is a Pimlico bundler method that bundles one signed user operation in its own bundle right away and returns its receipt in the same response.

Sends a signed user operation in its own bundle right away and returns its receipt in the same response. There is no mempool wait and no receipt polling. From TypeScript, use [`sendUserOperationSync`](/references/permissionless/reference/pimlico-actions/sendUserOperationSync), which also handles the errors below. Its page has the latency benchmarks.

Available on Base, BSC and Robinhood, with EntryPoint 0.7 and 0.8.

:::info[Contact us to enable it]
`pimlico_sendUserOperationNow` is enabled on request. [Contact us](https://cal.com/kristofgazso/20min) or email [support@pimlico.io](mailto\:support@pimlico.io) to turn it on for your API key and chains.
:::

## Usage

The parameters are the same as [`eth_sendUserOperation`](/references/bundler/endpoints/eth_sendUserOperation): the user operation and the EntryPoint address.

A [boosted user operation](/guides/boosted-paymaster/use-boosted-paymaster) on Base with EntryPoint 0.8: `maxFeePerGas` and `maxPriorityFeePerGas` are `0` and every paymaster field is empty. The gas is billed on your monthly invoice.

```json
{
  "jsonrpc": "2.0",
  "method": "pimlico_sendUserOperationNow",
  "params": [
    {
      "sender": "0x1068D0C20CeFD20725035B90Eb0c32BFA4057c12",
      "nonce": "0x1",
      "callData": "0xb61d27f6000000000000000000000000000000000000000000000000000000000000dead000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000",
      "callGasLimit": "0x7530",
      "verificationGasLimit": "0x186a0",
      "preVerificationGas": "0xea60",
      "maxFeePerGas": "0x0",
      "maxPriorityFeePerGas": "0x0",
      "signature": "0xaae4efeb36210ec5111608edb88b81bec6d3e0d21f7666f3b93a9b709ff1bfab14fa4b2f84f37ad1af7f88d61a4cd8b6884c14db9b8c8a01f1ab7520ba46caf71b"
    },
    "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108"
  ],
  "id": 1
}
```

## Returns

* **Type:** `RpcUserOperationReceipt`

The user operation receipt, once the user operation is included: the same object [`eth_getUserOperationReceipt`](/references/bundler/endpoints/eth_getUserOperationReceipt) returns. Numbers are hex.

`success: false` means the user operation was included but its call reverted inside the account. Its nonce is used.

On Base, the receipt arrives before its block is sealed, so `receipt.blockHash` can be all zeros. Use `blockNumber` and `transactionHash` instead.

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "userOpHash": "0xaa7e6f2050bbd8e8fc0053f3646dac0e2c13c9830172ba06efcb9f49b1e8ca9f",
    "entryPoint": "0x4337084d9e255ff0702461cf8895ce9e3b5ff108",
    "sender": "0x1068D0C20CeFD20725035B90Eb0c32BFA4057c12",
    "nonce": "0x1",
    "actualGasUsed": "0x162e9",
    "actualGasCost": "0x0",
    "success": true,
    "logs": [],
    "receipt": {
      "transactionHash": "0x7cbfae4b823e5b08ab18913d165f56c65d52d30fd6c140646cf5e1c10a990b30",
      "transactionIndex": "0x18",
      "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
      "blockNumber": "0x3289aeb",
      "from": "0x43370250bfc02C7F085cB105558DA41E9CDB2D79",
      "to": "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108",
      "cumulativeGasUsed": "0x19646c",
      "gasUsed": "0x104cb",
      "contractAddress": null,
      "logs": [
        {
          "logIndex": "0x1b",
          "transactionIndex": "0x18",
          "transactionHash": "0x7cbfae4b823e5b08ab18913d165f56c65d52d30fd6c140646cf5e1c10a990b30",
          "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
          "blockNumber": "0x3289aeb",
          "address": "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108",
          "data": "0x",
          "topics": [
            "0xbb47ee3e183a558b1a2ff0874b079f3fc5478b7454eacf2bfc5af2ff5878f972"
          ]
        },
        {
          "logIndex": "0x1c",
          "transactionIndex": "0x18",
          "transactionHash": "0x7cbfae4b823e5b08ab18913d165f56c65d52d30fd6c140646cf5e1c10a990b30",
          "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
          "blockNumber": "0x3289aeb",
          "address": "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108",
          "data": "0x00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000162e9",
          "topics": [
            "0x49628fd1471006c1482da88028e9ce4dbb080b815c9b0344d39e5a8e6ec1419f",
            "0xaa7e6f2050bbd8e8fc0053f3646dac0e2c13c9830172ba06efcb9f49b1e8ca9f",
            "0x0000000000000000000000001068d0c20cefd20725035b90eb0c32bfa4057c12",
            "0x0000000000000000000000000000000000000000000000000000000000000000"
          ]
        }
      ],
      "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000008000000000000000000010000000000000000000000000000020000000800000000000000000000000000000002000000000000000000000000000000000000000000020000000000000000000800000000000020000000000000000000000000000800000000008000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000002000000000000000000000000000001000000000000000000000000200000000010000020000000020000000000000000000000000000000000000000000000000000000800",
      "status": "0x1",
      "effectiveGasPrice": "0x5dd770"
    }
  }
}
```

## Errors

Errors are standard JSON-RPC errors. `error.data` is only set when a bundle was sent, and holds `userOpHash` and `transactionHash`. **If `data.transactionHash` is set, the user operation was sent:** track it instead of resending.

| Response | What happened | What to do |
| :--- | :--- | :--- |
| `-32602`, no `data` | Rejected, nothing was sent: invalid fields, gas limits too low, or a simulation failure such as `AA25 invalid account nonce` | Fix and resend |
| `-32602` "submitted but is not yet included", with `data` | Sent but not included in time. The bundler still tracks it and bumps its gas if it gets stuck | **Don't resend.** Poll [`eth_getUserOperationReceipt`](/references/bundler/endpoints/eth_getUserOperationReceipt) with `data.userOpHash` |
| `-32521` "reverted onchain", with `data` | The bundle landed but reverted, so it didn't execute the user operation. Another bundler may have included it first | Check [`eth_getUserOperationReceipt`](/references/bundler/endpoints/eth_getUserOperationReceipt), and resend only if there is no receipt |
| `-32603` | The bundler couldn't send the bundle | Resend |
| No response (network error, client timeout, 5xx) | Unknown: it may have been sent | Resend |

A signed user operation can execute at most once, because the EntryPoint checks its nonce. Resending never runs it twice: if the first send landed, the resend is rejected with `AA25`, and you can look up the receipt by `userOpHash`.

To avoid duplicate sends, set `retryCount: 0` on your viem transport. By default viem resends up to 3 times on timeouts and internal errors.

:::code-group
```json [Rejected]
{
    "jsonrpc": "2.0",
    "id": 1,
    "error": {
        "message": "bundle submission failed: FailedOp(0, AA25 invalid account nonce)",
        "code": -32602
    }
}
```

```json [Not included yet]
{
    "jsonrpc": "2.0",
    "id": 1,
    "error": {
        "message": "userOperation was submitted but is not yet included. Track it with eth_getUserOperationReceipt",
        "data": {
            "userOpHash": "0x…",
            "transactionHash": "0x…"
        },
        "code": -32602
    }
}
```

```json [Reverted]
{
    "jsonrpc": "2.0",
    "id": 1,
    "error": {
        "message": "bundle transaction 0x64deb43595ad19c86d823081c8878117f2536413ec6e3dbad661e24d484791ee reverted onchain",
        "data": {
            "userOpHash": "0xbcebbcd851d2a455454d9fdfc2a698a67e69ccd44a582ced92f914bf58615d25",
            "transactionHash": "0x64deb43595ad19c86d823081c8878117f2536413ec6e3dbad661e24d484791ee"
        },
        "code": -32521
    }
}
```
:::

## Nonces

* **No queue:** the user operation is simulated against the current chain state, so its nonce must be the account's current nonce for that key.
* **One at a time per key:** a user operation with nonce N+1, sent while N is in flight, is rejected with `AA25`. The response comes after inclusion, so send them one after another.
* **Base, next nonce right after a receipt:** the receipt arrives before its block is sealed, so nonce N+1 sent right after N's receipt can be rejected with `AA25 invalid account nonce`. Nothing is sent, so resend it after 1–2s.
* **Parallel sends:** to send in parallel from one account, use [different nonce keys](/guides/how-to/parallel-transactions).