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ZapSMTP / Docs / Emails

Reschedule an email

PATCH/v1/emails/{id}

Reschedule a scheduled email.

Requires a full-access or sending-access key.

Unknown ids return 409 not_cancellable, not 404.

Path parameters

idstringrequired
Scheduled email id

Body parameters

scheduled_atstringrequired
RFC 3339 or "in <n> <unit>" (see POST /emails). A time in the past dispatches as soon as possible. Limits: missing → 422 missing_required_field; unparsable or > 7 days ahead → 422 invalid_parameter

Errors

restricted_api_keyHTTP 403
this API key cannot manage this email (another domain or stream, or live mail with a test key)
not_cancellableHTTP 409
only scheduled emails can be updated
missing_required_fieldHTTP 422
invalid_parameterHTTP 422
PATCH/v1/emails/{id}
curl -X PATCH 'https://zapsmtp.xyz/v1/emails/019a1f2e-7c3b-7d41-9a52-0c4b8e6f1a23' \
  -H "Authorization: Bearer $ZAP_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "scheduled_at": "in 2 hours"
}'
Set ZAP_API_KEY in your environment.
Response 200 OK
{
  "object": "email",
  "id": "019a1f40-2b3c-7d4e-8f5a-6b7c8d9e0f12",
  "status": "scheduled",
  "last_event": "scheduled",
  "scheduled_at": "2026-10-23T09:00:00Z",
  "from": "Acme <hello@acme.com>",
  "to": [
    "jane@example.org"
  ],
  "subject": "Your weekly digest",
  "created_at": "2026-10-21T16:20:05.114Z"
}