Resend SMTP settings: smtp.resend.com, port 465, username resend
Resend SMTP: host smtp.resend.com, port 465 SSL (or 587/2465/2587), username literally "resend" and an API key as the password. Free tier (3,000/month, 100/day) and setup.
Resend outgoing mail server:
smtp.resend.com, port <code>465</code> (SSL/TLS) or <code>587</code> (STARTTLS) or <code>2465</code> (SSL/TLS) or <code>2587</code> (STARTTLS), username = resend (the literal string), password = an API key with sending access.
Resend SMTP settings at a glance
| Outgoing (SMTP) host | smtp.resend.com |
|---|---|
| Ports & encryption |
465 — SSL/TLS <em>(recommended)</em>587 — STARTTLS2465 — SSL/TLS2587 — STARTTLS |
| Username | resend (the literal string) |
| Password | an API key with sending access |
| Authentication | Created in API Keys; the From domain must be verified in Domains. |
How to set up Resend SMTP
- Domains → Add domain → add the DNS records → verify.
- API Keys → Create → Sending access.
- App settings: host smtp.resend.com, port 465, SSL/TLS, username resend, password = API key.
Sending limits
- Free tier: 3,000 emails per month and 100 per day, one domain; Pro from $20/month.
- DKIM/SPF/Return-Path records per domain.
Things that catch people out
- Free tier allows only one verified domain.
Common Resend SMTP errors
| Server reply | Meaning | Fix |
|---|---|---|
535 Authentication failed | Username not "resend" or key invalid. | Use the literal username resend. |
More codes: 535 authentication failed, 550 relay denied, 554 rejected as spam, connection timed out — or all SMTP error codes.
When Resend is not enough for your app
When a provider caps you or blocks a port, point the same app at QueenSMTP instead: host smtp.queensmtp.com, port 587 (STARTTLS) or 465 (SSL), your SMTP username and password from the dashboard. $5/year plus $0.10 per 1,000 emails, 100 free a day to test.
Get SMTP credentials — free to test Test Resend nowRelated settings
Resend SMTP — questions
smtp.resend.com on port 465 (SSL) or 587 (STARTTLS); username is the string resend and the password is an API key.
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