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On the recordRead 7 Oct 202612 facts
OpenSMTPD
Plans and prices
OpenSMTPD
Free
Server-side SMTP implementation; runs on supported Unix systems
Read 7 Oct 2026 · opensmtpd.org
On the record
- Delivery
- Supported delivery methods include LMTP, Maildir, mbox, mail delivery agent commands, and relaying to another SMTP server.man.openbsd.org · read 7 Oct 2026
- Filtering
- Mail filters can evaluate SMTP sessions at phases including connection, HELO/EHLO, sender, recipient, data, and commit.man.openbsd.org · read 7 Oct 2026
- License
- The project says the software is freely usable and reusable under an ISC license.opensmtpd.org · read 7 Oct 2026
- Mail handling
- It accepts matching messages into a mail queue and dispatches them according to configured actions.man.openbsd.org · read 7 Oct 2026
- Packaging
- The portability team adds code for other operating systems but does not package OpenSMTPD for them.opensmtpd.org · read 7 Oct 2026
- Purpose
- OpenSMTPD implements server-side SMTP and lets machines exchange email with systems that speak SMTP.opensmtpd.org · read 7 Oct 2026
- Queue encryption
- The configuration supports encrypting queue files with AES-256-GCM.man.openbsd.org · read 7 Oct 2026
- Security
- Project goals include careful validity checks on network input and privilege separation to mitigate possible security bugs.opensmtpd.org · read 7 Oct 2026
- Security reporting
- The project directs security issue reports to its private developers mailing list.opensmtpd.org · read 7 Oct 2026
- Support
- The project is volunteer-developed and is not backed by a commercial entity.opensmtpd.org · read 7 Oct 2026
- TLS
- Configuration supports STARTTLS and SMTPS for incoming connections, and TLS options for relaying mail.man.openbsd.org · read 7 Oct 2026
