What is Postal used for?

Postal is an open-source mail delivery platform for sending and receiving email, comparable to Sendgrid, Mailgun or Postmark but run on your own servers. It is a good fit for transactional email from your own servers and teams replacing Sendgrid or Mailgun.

Is Postal open source?

Yes. Postal is open source under the MIT licence. Its source code is on GitHub at postalserver/postal and is written mainly in Ruby.

Yes. Postal is open source, so the software itself is free to use.

Can I self-host Postal?

Yes. Postal can be self-hosted on your own server or infrastructure; there is no official hosted version.

What is Postal an alternative to?

Postal is an open-source alternative to SendGrid, Mailgun, Postmark and Amazon SES. Other open-source alternatives to SendGrid include Plunk, Notifuse and BillionMail.

Is Postal actively maintained?

Yes. The most recent commit to Postal was on 1 October 2026, and the latest release is 3.3.7, published on 3 June 2026. The project has 17k stars on GitHub.

Postal: open-source alternative to SendGrid, Mailgun

About Postal

Postal is a complete mail server for websites and web servers that handles both outgoing and incoming email. The project describes it as an open-source take on services such as Sendgrid, Mailgun and Postmark, ready to run on your own servers rather than rented as a hosted API.

It is written in Ruby and released under the MIT license. The project provides documentation with installation instructions, an FAQ and features list, a separate repository of installation tools, and community support through GitHub Discussions and Discord. Repository topics list Ruby, mail, SMTP and mail server.

Because it is self-hosted, Postal suits teams that want control over their own email delivery infrastructure instead of relying on a hosted provider, such as websites that send transactional messages.

Key features

Outgoing and incoming email handling
Self-hosted alternative to Sendgrid and Mailgun
SMTP mail server written in Ruby
Installation tools and documentation
Community support on Discord

Good fit for

→Transactional email from your own servers
→Teams replacing Sendgrid or Mailgun

Built with: Ruby
Tags: mail-server; smtp; email-delivery; transactional-email; self-hosted; ruby; sendgrid-alternative; mailgun-alternative

Postal: questions and answers

What is Postal used for?: Postal is an open-source mail delivery platform for sending and receiving email, comparable to Sendgrid, Mailgun or Postmark but run on your own servers. It is a good fit for transactional email from your own servers and teams replacing Sendgrid or Mailgun.
Is Postal open source?: Yes. Postal is open source under the MIT licence. Its source code is on GitHub at postalserver/postal and is written mainly in Ruby.
Is Postal free?: Yes. Postal is open source, so the software itself is free to use.
Can I self-host Postal?: Yes. Postal can be self-hosted on your own server or infrastructure; there is no official hosted version.
What is Postal an alternative to?: Postal is an open-source alternative to SendGrid, Mailgun, Postmark and Amazon SES. Other open-source alternatives to SendGrid include Plunk, Notifuse and BillionMail.
Is Postal actively maintained?: Yes. The most recent commit to Postal was on 1 October 2026, and the latest release is 3.3.7, published on 3 June 2026. The project has 17k stars on GitHub.