Trigger an automation now

POST

/api/v3/automations/{automationUniqueId}/actions/trigger

const url = 'https://api.tryletterhead.com/api/v3/automations/example/actions/trigger';
const options = {method: 'POST', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}

curl --request POST \
  --url https://api.tryletterhead.com/api/v3/automations/example/actions/trigger \
  --header 'Authorization: Bearer <token>'

Build this automation’s newsletter immediately and schedule it to send within the next minute or two, without waiting for the automation’s own schedule. This is a real send to the automation’s full audience.

Because of that, this endpoint is restricted to Letterhead staff: it authenticates as a signed-in user with a @tryletterhead.com or @whereby.us email address rather than a company API key, so it is not available to external integrations.

Authorizations

bearerAuth

Parameters

Path Parameters

automationUniqueId

required

string

The automation’s unique identifier.

Responses

200

200 OK

application/json

object

items

The letter that was just scheduled to send. See the Letters endpoints for the full field list.

object

message

string

total

integer

Example

{
  "items": {
    "uniqueId": "def456",
    "title": "Welcome Series - Step 1"
  },
  "message": "Newsletter \"Welcome Series - Step 1\" is scheduled to send at 2026-08-26 14:32:00 UTC.",
  "total": 10
}

Still can’t find what you need? Contact support.