Mark a project state as default

POST/api/v2/workspaces/{slug}/project-states/{pk}/mark-default/

Make this project state the workspace's default. A project created without a state_id starts in the default project state.

Exactly one project state has is_default: true. This call sets the flag on pk and clears it on the previous default in the same transaction, so there is never a moment with two defaults or none. Calling it on the state that is already the default changes nothing and returns 200.

This is a bodyless POST. The response is the project state in its usual read shape, with is_default: true.

Path Parameters

slug:requiredstring

The workspace slug. It appears in your Plane URLs. In https://app.plane.so/my-team/projects/, the slug is my-team.

pk:requiredstring (uuid)

The id of the project state to make the default.

Body Parameters

None. The endpoint takes no request body and ignores anything you send.

Response shaping

fields:optionalstring

Comma-separated list of fields to return. Unrequested keys are omitted from the response, not returned as null, so absent means "not requested" and null means "actually null". id always comes back whether or not you name it.

Pass all for every requestable field. An unknown name is a 400 that lists the valid set and suggests the closest match, so a typo can't silently cost you the saving.

Requestable here: color, created_at, created_by_id, description, external_id, external_source, group, id, is_default, name, sequence, updated_at, updated_by_id.

See Sparse fields.

Scopes

workspaces.project_states:write

Errors

Status	Code	Cause
400	invalid_request	The request could not be processed, for example a pk that isn't a valid UUID.
401	unauthorized	Missing or invalid credentials.
402	payment_required	Project states aren't included in the workspace's plan, or are turned off in its settings.
403	forbidden	Your role or token scope can't update project states.
404	not_found	No such project state or workspace, or it's outside your tenant.
406	not_acceptable	The Accept header asks for a representation the API can't produce.
409	governance_migration_in_progress	A governance migration is running, so the workspace is read-only. Retry after it finishes.
413	payload_too_large	The request body is over the size limit.
415	unsupported_media_type	The Content-Type isn't one this endpoint accepts.
429	rate_limited	Throttled. Honor the Retry-After header before retrying.

Mark a project state as default

curl -X POST \
  "https://api.plane.so/api/v2/workspaces/my-team/project-states/a41d6f38-0e2c-4b97-85a3-7f1e9d2c6b50/mark-default/" \
  -H "X-Api-Key: $PLANE_API_KEY"

import requests

response = requests.post(
    "https://api.plane.so/api/v2/workspaces/my-team/project-states"
    "/a41d6f38-0e2c-4b97-85a3-7f1e9d2c6b50/mark-default/",
    headers={"X-Api-Key": "your-api-key"},
)
print(response.json()["is_default"])

const response = await fetch(
  "https://api.plane.so/api/v2/workspaces/my-team/project-states" +
    "/a41d6f38-0e2c-4b97-85a3-7f1e9d2c6b50/mark-default/",
  {
    method: "POST",
    headers: { "X-Api-Key": "your-api-key" },
  },
);
const data = await response.json();

Response200

{
  "id": "a41d6f38-0e2c-4b97-85a3-7f1e9d2c6b50",
  "name": "Planning",
  "description": "",
  "color": "#60646C",
  "group": "planning",
  "sequence": 25000,
  "is_default": true,
  "external_id": null,
  "external_source": null,
  "created_at": "2026-01-14T09:22:41.478363Z",
  "updated_at": "2026-01-14T09:22:41.478363Z",
  "created_by_id": "16c61a3a-512a-48ac-b0be-b6b46fe6f430",
  "updated_by_id": "16c61a3a-512a-48ac-b0be-b6b46fe6f430"
}

updated_at doesn't move

Plane swaps the default flag with a direct update, so neither project state's updated_at nor its updated_by_id changes. Read is_default, not the timestamps, to see which state is the default.