Postal is an open source alternative to SendGrid and Mailgun. Open source mail delivery platform for incoming and outgoing e-mail, self-hosted on Docker, a SendGrid or Mailgun alternative on your own servers. MIT licensed, 16.7k GitHub stars, self-host with Docker, and last released 2026-06-03.
Open source mail delivery platform for incoming and outgoing e-mail, self-hosted on Docker, a SendGrid or Mailgun alternative on your own servers.
How to start todayIn the product
Should you switch?
Teams that want a full featured open source mail delivery platform for incoming and outgoing e-mail, positioned by the project as a Sendgrid, Mailgun or Postmark alternative you run on your own servers, with a Docker-based install path.
You want a fully managed transactional e-mail service without operating your own server. Running your own mail server is not for everyone, and you remain responsible for configuring DNS records and maintaining the platform, IP reputation, and deliverability.
Self-hosting requires you to manage IP reputation yourself and configure SPF, DKIM, DMARC, and PTR reverse lookup correctly, with IP warm-up recommended to reach good deliverability. A reverse proxy (Caddy, nginx, Apache, or HAProxy) is required for SSL termination, and the platform is community-supported via GitHub Discussions and Discord.
Support the creator
Support this project directly once our USDC payment option launches.
USDC is a trademark of Circle. Button indicates a payment option.
Community proof
"I now use Postal Server for all my SaaS, which is self-hosted via docker, and has all those those features. The good thing is your maintain the IP reputation yourself and your not paying exorbitant prices when sending large volumes of transactional emails (really it's just the cost of the server you install it on)."
"> Nobody wants to run a mail server in 2026. We do, and thats why we use Postal [1]. The more SaaS applications that self-host email the better. It forces the big guys, ie Microsoft, to improve their blocklists and not lazily block entire ranges. Yes its work contacting them occasionally, but it keeps the internet open."
Maintenance health
Can you do it today?
postal initialize && postal make-user && postal startGitHub
More in Email
See all in Email ->Find more Open Source solutions at thereisanopensourceforthat.com
Topics
