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