---
title: "Make a topic the tenant default."
method: POST
path: "/topics/{topicId}/default"
tags: ["Topics"]
---

# Make a topic the tenant default.

`POST /topics/{topicId}/default`

## Request

- Base URL: `https://api.maildroppa.com` (the document declares no server; this is the origin it was published from)
- URL: `https://api.maildroppa.com/topics/{topicId}/default`
- Auth: API key in header `X-API-Key`

Only active topics can become the default; existing assignments stay unchanged.

## Path parameters

- `topicId` string, uuid, required

## Response `200`

Default topic changed.

- Topic: Subscription topic that readers can subscribe to and unsubscribe from individually.
  - `id` string, uuid
  - `label` string: Label shown to readers on forms and the preference page.
  - `description` string: Optional description shown to readers.
  - `position` integer: Catalog position; gaps are allowed.
  - `status` 'ACTIVE' | 'ARCHIVED'
  - `archivedAtUtc` string, date-time
  - `defaultTopic` boolean: Whether this is the tenant default topic.
  - `subscribedCount` integer: Subscribers currently subscribed to the topic.
  - `optedOutCount` integer: Subscribers who opted out of the topic themselves.
  - `enrollmentRunning` boolean: Whether existing subscribers are currently being enrolled into the topic.
  - `enrollment` TopicEnrollmentDto
    - `status` 'RUNNING' | 'COMPLETED' | 'FAILED'
    - `startedAtUtc` string, date-time
    - `addedSubscriberCount` integer

## Other responses

- `400`: Invalid topic state or active topic limit reached.
- `401`: Not Authorized
- `403`: Not Allowed
- `404`: Topic not found in this account.
- `409`: Subscriber bulk operation prevents catalog changes.
- `428`: Accept the customer agreements in the app before using API keys.

---

[API](https://skmtc.dev/maildroppa/apis/maildroppa-api-beta.md) · [All operations](https://skmtc.dev/maildroppa/apis/maildroppa-api-beta/llms.txt) · [OpenAPI document](https://skmtc.dev/maildroppa/apis/maildroppa-api-beta/revisions/a9f5a3fd1fb0?raw)