Brevo (ex-Sendinblue)
SMTP Server: smtp-relay.brevo.com
Port: 587 (TLS/SSL) or 465 (SSL)
Authentication Required: Yes (Username/Password)
Free Tier: 300 emails/day
Notes: Very easy to set up. No need for OAuth. Ideal for lightweight alerting
SMTP2Go
SMTP Server: mail.smtp2go.com
Port: 2525 (recommended), 25, 587, or 465 (SSL)
Authentication Required: Yes (Username/Password)
Free Tier: 1,000 emails/month
Notes: Extremely simple dashboard. Allows server-based authentication without complex setup.
Mailjet
SMTP Server: in-v3.mailjet.com
Port: 587 or 465
Authentication Required: Yes (Username/Password)
Free Tier: 6,000 emails/month (200/day limit)
Notes: Easy registration. Supports quick SMTP relay configuration.
hMailServer (Self-Hosted)
Setup: Install hMailServer on a Windows machine
SMTP Server: Your server IP
Port: 25 (by default, customizable)
Authentication Required: Optional (depending on config)
Free Tier: Fully self-hosted, unlimited
Notes: If your server has a public IP and proper DNS records (like PTR records), you can act as your own SMTP server. However, mail delivery may be more complex due to spam protections (DKIM, SPF, DMARC).
Postmark (for Testing / Limited Usage)
SMTP Server: smtp.postmarkapp.com
Port: 587
Authentication Required: Yes (Server API token as username)
Free Tier: 100 emails/month for testing
Notes: Strictly for production apps, but their free tier can be used for limited alerting during test periods.
Always verify if your server firewall or ISP blocks outbound port (25 or 587 or 465 or 2525)
Some providers require validating your "From" email address or domain.
Use SSL/TLS when possible to secure alert email transmissions.
Neverfail supports authenticated SMTP and SSL encryption out-of-the-box.
Best Overall: Sendinblue (Brevo) for ease of use and reliability.
Best for High Volume (Free Tier): Mailjet.
Best for Full Control: Self-hosted hMailServer (for technical customers comfortable managing their own SMTP relay).