SMTP
Connect SMTP-only tools to Lumail transactional email.
Use Lumail SMTP when an application can only send through SMTP and cannot call POST /api/v1/emails directly.
The endpoint is designed for low-volume transactional email: authentication codes, magic links, password resets, account invitations, receipts, and operational notifications. SMTP messages are accepted by the Lumail SMTP adapter, authenticated with a Lumail API token, then queued through the transactional priority lane.
Connection Settings
| Setting | Value |
|---|---|
| Host | smtp.lumail.io |
| Port | 587 |
| Security | STARTTLS |
| Username | Your organization slug, or any label |
| Password | A Lumail API token |
| From | An address on a verified Lumail domain |
The password is not your Lumail account password. Create an API token from Settings -> API Tokens and store it in your application's secret manager.
Setup Checklist
- Verify the sending domain in Lumail.
- Create a Lumail API token in the same organization.
- Configure your app to use
smtp.lumail.ioon port587with STARTTLS. - Use a
Fromaddress on the verified domain. - Send one test email before enabling the integration in production.
Test-mode recipients. Fixture addresses such as
[email protected]never send real email. See Test-mode recipients.
For the full setup flow, use the SMTP transactional email tutorial.
Supabase Auth
Supabase Auth custom SMTP can use these values:
Host: smtp.lumail.io
Port: 587
Security: STARTTLS
Username: your-org-slug
Password: lum_your_api_token
Sender email: [email protected]If your application supports HTTP hooks, prefer POST /api/v1/emails. The HTTP API returns structured errors and avoids SMTP/MIME parsing.
Related Documentation
- SMTP transactional email tutorial - End-to-end setup for an organization
- SMTP endpoint reference - Response codes, limits, and behavior
- Create an API token - Generate the SMTP password
- Email domains - Verify the sender domain