Freedom251 › Mail Server Software
OpenSMTPD
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| OpenSMTPD | FREE · Server-side SMTP implementation; runs on supported Unix systems | Free |
As opensmtpd.org lists them, read 7 Oct 2026. The maker's own page has the final word.
Facts from OpenSMTPD's own pages
- Delivery
- Supported delivery methods include LMTP, Maildir, mbox, mail delivery agent commands, and relaying to another SMTP server. · man.openbsd.org, 7 Oct 2026
- Filtering
- Mail filters can evaluate SMTP sessions at phases including connection, HELO/EHLO, sender, recipient, data, and commit. · man.openbsd.org, 7 Oct 2026
- License
- The project says the software is freely usable and reusable under an ISC license. · opensmtpd.org, 7 Oct 2026
- Mail handling
- It accepts matching messages into a mail queue and dispatches them according to configured actions. · man.openbsd.org, 7 Oct 2026
- Packaging
- The portability team adds code for other operating systems but does not package OpenSMTPD for them. · opensmtpd.org, 7 Oct 2026
- Platforms
- The portable release lists OpenBSD, FreeBSD, NetBSD, DragonFlyBSD, Linux, SmartOS, and macOS; support depends on package maintainers providing regular development feedback. · opensmtpd.org, 7 Oct 2026
- Purpose
- OpenSMTPD implements server-side SMTP and lets machines exchange email with systems that speak SMTP. · opensmtpd.org, 7 Oct 2026
- Queue encryption
- The configuration supports encrypting queue files with AES-256-GCM. · man.openbsd.org, 7 Oct 2026
- Security
- Project goals include careful validity checks on network input and privilege separation to mitigate possible security bugs. · opensmtpd.org, 7 Oct 2026
- Security reporting
- The project directs security issue reports to its private developers mailing list. · opensmtpd.org, 7 Oct 2026
- Support
- The project is volunteer-developed and is not backed by a commercial entity. · opensmtpd.org, 7 Oct 2026
- TLS
- Configuration supports STARTTLS and SMTPS for incoming connections, and TLS options for relaying mail. · man.openbsd.org, 7 Oct 2026
Where OpenSMTPD stands on Freedom251
- Mail Server Software#19 of 34