# email.sent

> Fires when an email is accepted by MailBlastr and handed off for delivery to the recipient's mail server.

The `email.sent` event fires whenever the **API request to send an email was successful**. MailBlastr has accepted the message and will attempt to deliver it to the recipient's mail server — a successful delivery is later reported by [`email.delivered`](https://www.mailblastr.com/docs/webhooks/emails/delivered).

Every payload follows the shared envelope: a top-level `type`, `created_at`, and a `data` object with the event-specific fields.

```json
{
  "type": "email.sent",
  "created_at": "2026-06-22T23:41:12.126Z",
  "data": {
    "campaign_id": "8b146471-e88e-4322-86af-016cd36fd216",
    "created_at": "2026-06-22T23:41:11.894719+00:00",
    "email_id": "49a3999c-0ce1-4ea6-ab68-afcd6dc2e794",
    "message_id": "<111-222-333@email.example.com>",
    "from": "Acme <onboarding@example.com>",
    "to": ["recipient@example.com"],
    "subject": "Sending this example",
    "template_id": "43f68331-0622-4e15-8202-246a0388854b",
    "tags": {
      "category": "confirm_email"
    }
  }
}
```

**Payload**

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `type` | string | No | The event type that triggered the webhook. |
| `created_at` | string | No | ISO 8601 timestamp when the webhook event was created. |
| `data` | object | No | Event-specific data. The fields below live inside this object. |
| `data.campaign_id` | string | No | Identifier for the campaign, if the email was sent as part of one. |
| `data.created_at` | string | No | ISO 8601 timestamp when the email was created. |
| `data.email_id` | string | No | Unique identifier for this email. |
| `data.message_id` | string | No | RFC Message-ID header value for the email. |
| `data.from` | string | No | Sender address as passed at send time; may include a display name (e.g. `Name <email@example.com>`). |
| `data.to` | string[] | No | Recipient email address(es). |
| `data.subject` | string | No | Email subject line. |
| `data.template_id` | string | No | Identifier of the template used, if applicable. |
| `data.tags` | object | No | Object of tag key-value pairs associated with the email. |

> **Note:** This is one of several events MailBlastr can deliver. See the full list of [webhook event types](https://www.mailblastr.com/docs/webhooks/events).