---
title: "Broadcast a signed zero-fee ERC-4337 v0.7 UserOperation"
method: POST
path: "/v2/bundler/user-operations"
tags: ["Bundler"]
---

# Broadcast a signed zero-fee ERC-4337 v0.7 UserOperation

`POST /v2/bundler/user-operations`

## Request

- Base URL: `https://api.peer.xyz`
- URL: `https://api.peer.xyz/v2/bundler/user-operations`
- Auth: HTTP bearer

## Request body

- object
  - `chainId` union, required
    - 8453
    - 56
    - 4663
  - `idempotencyKey` string, uuid, required
  - `userOperation` object, required
    - `sender` string, required
    - `nonce` string, required
    - `callData` string, required
    - `callGasLimit` string, required
    - `verificationGasLimit` string, required
    - `preVerificationGas` string, required
    - `maxFeePerGas` '0x0', required
    - `maxPriorityFeePerGas` '0x0', required
    - `signature` string, required
    - `eip7702Auth` object
      - `address` string, required
      - `chainId` string, required
      - `nonce` string, required
      - `yParity` string, required
      - `r` string, required
      - `s` string, required

## Response `202`

UserOperation broadcast

- object
  - `success` boolean, required
  - `message` string, required
  - `responseObject` object
    - `chainId` integer, required
    - `userOperationHash` string, required
    - `transactionHash` string, required
    - `timingsMs` object, required
      - `authentication` number, required
      - `validation` number, required
      - `queue` number, required
      - `authorization` number, required
      - `feeQuote` number, required
      - `sponsorNonce` number, required
      - `signing` number, required
      - `broadcast` number, required
      - `total` number, required
  - `statusCode` number, required
  - `errorCode` string

## Other responses

- `400`: Invalid UserOperation
- `403`: Sender is not the authenticated embedded wallet
- `409`: Idempotency key conflict
- `502`: Submission failed
- `503`: Bundler unavailable

## Changes

- **2026-09-13** `8d9a34e0e5d2`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/peer/apis/swagger-api/changes/v2/bundler/user-operations/post.md)

---

[API](https://skmtc.dev/peer/apis/swagger-api.md) - [All operations](https://skmtc.dev/peer/apis/swagger-api/llms.txt) - [OpenAPI document](https://skmtc.dev/peer/apis/swagger-api/revisions/ef91955315e2?raw)