KMail
Verified working Sep 19, 2026
A KDE desktop mail client with encryption and Kontact integration.
KMail is KDE’s desktop email client and the mail component of the Kontact personal information manager. It supports common mail protocols, message search and filtering, spam-checker integration, imports from other clients, and built-in support for OpenPGP, PGP/MIME, and S/MIME email encryption.
Why it stands out
- Deep integration with KDE’s Kontact suite, so mail, address book data, and calendar invitations work together.
- Supports several email encryption standards natively instead of relying only on add-ons.
- Can search IMAP folders and apply advanced filters, useful for large server-side mailboxes.
- Works with external spam tools such as SpamAssassin and Bogofilter rather than locking users into one filter.
- Includes migration and backup documentation for users moving from other mail clients.
Good to know
- The UserBase page itself is marked as proposed for deletion and points users toward newer KDE application pages, so it may not be the most current reference.
- The download notes emphasize Linux distribution repositories and tarballs; Windows support is described as outdated and needing contributors.
- Flatpak availability is described as forthcoming on this page rather than clearly available from it.
Under the radar: If you land on this UserBase article for installation details, also check the Kontact download page or apps.kde.org because this wiki page is flagged as potentially being replaced.
Photos
KDE and Linux desktop users can manage email locally while keeping mail, calendar invitations, and contacts tied into Kontact. Connect to IMAP, POP3, and SMTP accounts with SSL/TLS login options. Read and send encrypted mail using OpenPGP, PGP/MIME, or S/MIME. Import mail from other clients and set up backups for existing mail archives. Accept meeting invitations from email and have them appear in the KDE calendar workflow.
IMAP, POP3, and SMTP support; NTLM and Kerberos authentication; SSL/TLS logins; as-you-type and on-demand spell checking; HTML and plain-text message viewing; OpenPGP, PGP/MIME, and S/MIME support; spam-filter integration; message tags and flags; mailing-list tools; attachment compression; KWallet password storage; Kontact/KOrganizer groupware integration.
Alternative listings
Self-hosted webmail with a full IMAP inbox in the browser.
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Similar sites elsewhere
- Mozilla Thunderbird — thunderbird.net
- Evolution — wiki.gnome.org/Apps/Evolution
- Claws Mail — claws-mail.org
- Mutt — mutt.org
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