---
title: "Cancel a single scheduled message"
method: POST
path: "/cancel-sms/"
tags: ["Campaigns"]
---

# Cancel a single scheduled message

`POST /cancel-sms/`

## Request

- Base URL: `http://api.smsfusion.com.au`
- URL: `http://api.smsfusion.com.au/cancel-sms/`
- Auth: one of:
  - API key in query parameter `key`
  - HTTP basic

Best-effort cancel of a not-yet-sent delayed message. Success is only reported on a confirmed delete of the queued send job; if the sending worker reserves the job first, the cancel fails honestly and the message still sends. Reliable only while scheduled delay remains

## Query parameters

- `key` string, required
- `id` integer, required

## Response `200`

Message will not send - confirmed cancel

- object
  - `success` boolean
  - `transactId` integer

## Other responses

- `400`: CANCEL_FAILED - message not found, already sent, too late / not a delayed send, or already being sent (race lost)
- `405`: Method not allowed - POST only (checked before auth on this endpoint)

---

[API](https://skmtc.dev/smsfusion/apis/sms-fusion-api.md) · [All operations](https://skmtc.dev/smsfusion/apis/sms-fusion-api/llms.txt) · [OpenAPI document](https://skmtc.dev/smsfusion/apis/sms-fusion-api/revisions/a88b2793a6e9?raw)