Piler is free, open-source email archiving software you host yourself, also known as mailpiler. It stores mail with deduplication and encryption and makes it searchable for compliance. A paid, also self-hosted Piler Enterprise edition starts at EUR 400 for the first year for up to 10 users.
The bottom line
A strong free choice for IT teams that can self-host; others should trial Enterprise or use a hosted archive.
6.6
Our score
6.6 / 10
Conversion Gems editorial verdict
Free; Enterprise from EUR 400 first year
Features7/10
7 - deduplication, encryption, full-text search, retention rules and LDAP/SSO; AI search and legal hold need Enterprise.
Value9/10
9 - the open-source edition is free under GPLv3; Enterprise starts at EUR 400 for the first year.
Ease of use4/10
4 - self-hosted on a server or Docker; setup needs Linux and mail server skills.
Ecosystem6/10
6 - imports from IMAP, POP3, Office 365 and Google, plus LDAP and SSO; few other integrations listed.
Support5/10
5 - GitHub and docs for open source; Enterprise adds 14 days of email support and paid plans.
What it really is
Free, self-hosted email archiving software with a paid Enterprise edition.
Our take
Piler does one job well: it captures your company's email, stores it once, and makes it searchable for audits and lost-message requests. The open-source edition is free and still maintained, with a release in June 2026. The trade-off is effort. You need a server and someone comfortable with Linux, and help comes from GitHub unless you buy Enterprise.
Why we rate it
It gives you a full email archive with search, retention and encryption at no license cost.
The catch
You host and maintain it yourself, and free support is community-only.
Best for
IT teams that can run Linux servers
Companies with email retention rules
Budget-limited organizations
Not good for
Teams with no server administrator
Anyone who wants a fully hosted archive
Buyers who need US-dollar contracts and long vendor support
Friction report
Time to value
High: install on a server or Docker, configure mail capture and secure it.
Scale breakpoint
Large archives need more servers; on Enterprise each worker node adds a full license fee.
Walled garden
Low: open source, and Enterprise says data exports in standard EML format.
Piler editions and pricing
Edition / users
First year
Yearly renewal
Notes
Open source
Free
Free
GPLv3, self-hosted, community support
Enterprise 1-10
EUR 400
EUR 150
1 server, unlimited emails, all features
Enterprise 11-50
EUR 800
EUR 250
1 server
Enterprise 51-99
EUR 1,200
EUR 400
1 server
Enterprise 100-199
EUR 1,500
EUR 500
1 server
Enterprise 200-299
EUR 2,000
EUR 650
1 server
From Piler's GitHub license and Piler Enterprise's pricing page, checked 4 October 2026. Extra worker nodes cost the same as the base license; frontend nodes EUR 300/year.
Frequently Asked Questions
Piler, also called mailpiler, is open-source email archiving software. It captures and stores a company's email with deduplication and encryption, and lets users search the archive for compliance and recovery.
Yes. The open-source edition is free under the GPLv3 license. Piler Enterprise is paid, from EUR 400 for the first year and EUR 150 a year after for up to 10 users (checked 4 October 2026).
First year and yearly renewal per server: 1-10 users EUR 400/150, 11-50 EUR 800/250, 51-99 EUR 1,200/400, 100-199 EUR 1,500/500, 200-299 EUR 2,000/650 (checked 4 October 2026).
Yes. The open-source project lists Office 365 and Google Apps imports, plus IMAP, POP3 and EML or Maildir files.
Piler Enterprise has a 30-day free trial with no credit card. The open-source edition is free to download from GitHub (checked 4 October 2026).
Piler alternatives
Other backup and email security tools in our directory:
ZixCorp Secure Email: Hosted email encryption and compliance service instead of a self-run archive.
