GFI KerioConnect vs Zimbra (2026): which should you pick?

GFI KerioConnect

• Organizations that want to run their own mail server
• Managed service providers, for which a separate MSP licensing option is listed
• Companies that need AI email help without sending data to a cloud service

Zimbra

• Companies and schools that need to keep email on servers they control
• Hosting providers offering white-labeled email to customers
• Teams moving off Microsoft Exchange who want Outlook compatibility

GFI KerioConnect

• No prices are published; the Buy now page sends visitors to a certified GFI reseller for a quote.
• It is a server product that the buyer installs and administers, not a hosted mailbox service.
• The product is now branded GFI KerioConnect and its pages sit on gfi.ai.

Zimbra

• Pricing is not published; Zimbra is licensed, and renewals go through an account manager.
• The FAQ calls the Open Source Edition end of life, with no updates or support.
• Features such as backup and restore, Zimbra Office and large-scale mobile sync need the commercial license.
• Chat and real-time collaboration are protected in transit only, not end-to-end encrypted.

GFI KerioConnect

Mail, calendar and collaboration

Email sits beside shared calendars, contacts, tasks, notes, shared and public folders, and room booking with attendee availability.

Client and mobile support

Works with Outlook on Windows and Mac, native Mac apps and other IMAP or POP clients. Phones sync by Microsoft ActiveSync or IMAP, CalDAV and CardDAV.

Local AI features

The AI edition summarizes emails, drafts replies and flags phishing or compliance risks, and the vendor says it runs on on-premise models with no cloud APIs.

Built-in security

SSL encryption, S/MIME, spam filtering, an antivirus engine, attack blocking, automated backup with granular restore and server-wide archiving.

Chat

Integrated instant messaging is XMPP-compatible, so third-party chat apps can connect, with online status for colleagues.

Zimbra

Mail, calendar and contacts

A web client with advanced and attachment search, personal and global address lists, group and resource scheduling, and tasks.

Two editions

Zimbra Daffodil (v10) needs a license, sold as Professional or Standard. Professional has additional features over Standard.

Desktop and mobile access

Zimbra Desktop for Windows, macOS and Linux, a Connector for Outlook on Windows, and ActiveSync on iOS and Android.

Standards-based clients

Works with IMAP, POP, CalDAV and CardDAV, so Thunderbird, Apple Mail and similar clients can connect.

Security and admin controls

Built-in anti-spam and antivirus, two-factor sign-in, LDAP or Active Directory, SAML sign-in and delegated administration.

Deployment options

Install on your own servers, run it in the cloud on AWS or OCI, or use a hosting partner, with multiple domains per install.

GFI KerioConnect

Pricing could not be confirmed. See gfi.ai.

Zimbra

Pricing could not be confirmed. See zimbra.com.