Resend event: email.sent means accepted, not delivered

TL;DR

This event means the API request was successful and Resend will attempt to deliver the message to the recipient's mail server. Delivery has not happened yet.

Steps

1. Record the email_id from data against your own message record. This is the handle every later event (delivered, bounced, opened) will reference.
2. Mark your message as queued, not sent. Your UI copy should say "sending" or "queued," never "delivered."
3. Do not notify the sender or trigger downstream flows that assume the recipient has the email.
4. Reading email.sent as delivery confirmation. Between this event and email.delivered, the email can bounce, fail, or get suppressed. If you mark orders confirmed, receipts issued, or notifications complete on email.sent, you will lie to users whenever delivery fails. The only event that proves the mail server got it is email.delivered.

When to use

You are seeing this: This event means the API request was successful and Resend will attempt to deliver the message to the recipient's mail server. Use this skill when you run into "Resend event: email.sent means accepted, not delivered".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Resend's event reference says email.sent occurs whenever the API request was successful, and Resend will attempt to deliver the message to the recipient's mail server. Verified live at https://resend.com/docs/webhooks/event-types.