Optionally, you can configure an SMTP server to send transactional emails. These are used for password resets, user invitations, and more.
-
PHOENIX_SMTP_HOSTNAME: The SMTP hostname to use for sending password reset emails.
-
PHOENIX_SMTP_PORT: The SMTP port. Defaults to
587. -
PHOENIX_SMTP_USERNAME: The SMTP username.
-
PHOENIX_SMTP_PASSWORD: The SMTP password.
-
PHOENIX_SMTP_MAIL_FROM: The
fromaddress in the emails. Defaults tonoreply@arize.com. -
PHOENIX_SMTP_VALIDATE_CERTS: Whether to validate the SMTP server’s certificate. Defaults to
true.
Example usage:
These settings are required for password reset flows when authentication is enabled in Phoenix.
FAQ#
Which SMTP service should I use?
- It is recommended to use a reputable SMTP service for transactional emails to ensure delivery and prevent abuse. If you do not have a preferred service from your cloud provider, consider providers like Resend, Mailgun, Sendgrid, or Postmark, which are easy to set up and offer generous free tiers.

