Fires when a spam complaint is received from an ISP feedback loop (for example Gmail or Yahoo).

​
Payload

{
  "id": "evt_xxxxx",
  "event": "email.complained",
  "timestamp": "2026-03-28T10:00:00Z",
  "data": {
    "message_id": "msg_email_xxxx",
    "channel_id": "ch_email_yyyy",
    "to": "jana@example.com",
    "complained_at": "2026-03-28T10:00:00Z"
  }
}
​
data.message_id
string
Identifier of the message associated with the complaint.
​
data.channel_id
string
Email channel used for the send.
​
data.to
string
Recipient address that issued the complaint.
​
data.complained_at
string
ISO 8601 time when the complaint was recorded.
Complaints automatically suppress the contact from future NEWSLETTER sends.