Overview The Mail Send API returns (queued) — it does NOT confirm delivery. To know what happened to an email, use Event Webhooks. Enable: SendGrid Console Settings Mail Settings Event Notification --- Event Types Delivery Events | Event | Meaning | |-------|---------| | | SendGrid accepted and will attempt delivery | | | Temporary failure — SendGrid will retry | | | Recipient's mail server accepted the message | | | Permanent failure — address invalid or rejected | | | SendGrid will not deliver (suppression, invalid, spam) | Engagement Events | Event | Meaning | |-------|---------| | | Recip…