email.failed
Event triggered whenever the email failed to send due to an error.
This event is triggered when there are issues such as invalid recipients, API key problems, domain verification issues, email quota limits, or other sending failures.
Response Body Parameters
Section titled “Response Body Parameters”All webhook payloads follow a consistent top-level structure with
event-specific data nested within the data object.
-
type(string) — The event type that triggered the webhook (e.g.,email.failed). -
created_at(string) — ISO 8601 timestamp when the webhook event was created. -
data(object) — Event-specific data containing detailed information about the event. The data object for theemail.failedevent contains the following parameters:
object parameters
broadcast_id(string) — Unique identifier for the broadcast campaign (if applicable)created_at(string) — ISO 8601 timestamp when the email was createdemail_id(string) — Unique identifier for the specific emailmessage_id(string) — RFC Message-ID header value for the emailfrom(string) — Sender's email address. For sent events, this matches the value passed at send time and may include a display name (e.g.,Name <email@domain.com>). For received events, this is the bare email address only; the display name from the originalFrom:header is preserved inheaders.fromon the retrieve endpoint.to(array) — Array of impacted recipient email addressessubject(string) — Email subject linetemplate_id(string) — Unique identifier for the template used (if applicable)tags(Record<string, string>) — Object of tag key-value pairs associated with the email.
Example:
{
"category": "welcome",
"user_id": "1234567890"
}failed(object) — Failure details
failed object
reason(string) — Reason for the email failure (e.g.,reached_daily_quota)
{
"type": "email.failed",
"created_at": "2026-11-22T23:41:12.126Z",
"data": {
"broadcast_id": "8b146471-e88e-4322-86af-016cd36fd216",
"created_at": "2026-11-22T23:41:11.894Z",
"email_id": "56761188-7520-42d8-8898-ff6fc54ce618",
"message_id": "<111-222-333@email.example.com>",
"from": "Acme <onboarding@resend.dev>",
"to": ["delivered@resend.dev"],
"subject": "Sending this example",
"template_id": "43f68331-0622-4e15-8202-246a0388854b",
"failed": {
"reason": "reached_daily_quota"
},
"tags": {
"category": "confirm_email"
}
}
}