---
title: "Changes to Send a transactional email"
method: POST
path: "/api/projects/{project_id}/messaging_templates/{id}/send/"
---

# Changes to Send a transactional email

`POST /api/projects/{project_id}/messaging_templates/{id}/send/`

> Every recorded change to this operation, newest first.
> 53 revisions in range; 1 not diffed.

## Timeline

Changed in 2 of 53 revisions.

- **2026-10-21** `e263ffc38ef5`: 4 info
- **2026-10-16** `405eae87d089`: 1 info

## Changes

- **2026-10-21** `e263ffc38ef5`: 4 info
  - added the new optional `header` request parameter `Idempotency-Key`
  - added the non-success response with the status `409`
  - added the non-success response with the status `422`
  - added the required property `replayed` to the response with the `202` status
- **2026-10-16** `405eae87d089`: 1 info
  - endpoint added

---

[Operation](https://skmtc.dev/posthog/apis/posthog-api/docs/api/projects/:project_id/messaging_templates/:id/send/post.md) · [API](https://skmtc.dev/posthog/apis/posthog-api.md) · [Page](https://skmtc.dev/posthog/apis/posthog-api/changes/api/projects/:project_id/messaging_templates/:id/send/post)