KMail is an email client included with the KDE desktop. It is the email component of Kontact, a integrated personal information manager.
Kmail supports folders, filtering, viewing HTML mail, and international character sets. It can also handle IMAP, dIMAP, POP3, and local mailboxes for incoming mail. It can send mail via SMTP or sendmail.
Importantly, KMail supports the OpenPGP standard and can automatically encrypt, decrypt, sign, and verify signatures of email messages and its attachments via either the inline or OpenPGP/MIME method of signing/encryption.
Key Features
- Maildir support.
- Address book.
- Expiry of old messages.
- Automatic encryption using OpenPGP (PGP or GnuPG).
- Supported protocols: POP3, IMAP (both also work with SSL and TLS).
- SSL/TLS support for POP3.
- Pipelining for POP3 and SMTP (faster mail download on slow responding networks).
- On-demand downloading or deleting without downloading of big mails on a POP3 server.
- SMTP authentication.
- SMTP over SSL/TLS.
- DIGEST-MD5 authentication.
- Nested mail folders.
- Powerful mail filters.
- Mailing list aware folders.
- Drafts folders.
- Full support for mails in all languages and charsets supported by Qt.
- Import of other mail clients’ folders.
- Search dialog.
- Support for reading HTML mails.
- Editor supports spell checking, undo/redo.
- Threaded messages view.
- Multiple identities.
- Colorfied indenting (i.e. text that’s quoted has a different color).
- Background sending and downloading of mail.
- KDE integration such as drag and drop.
- Automatic popup address completion (similar to Konqueror).
- Support for custom colors and fonts.
- Mail bouncing capability (anti-spam).
- UTF-7 support.
- PGP/MIME (RFC 3156) support for GnuPG users.
- S/MIME support.
- Optional compression of attachments.
- Import mail from Evolution 2.x, Opera and Thunderbird.
Website: apps.kde.org/kmail2
Support: FAQ, GitHub Code Repository
Developer: KDE
License: GNU General Public License

KMail is written in C++. Learn C++ with our recommended free books and free tutorials.
Related Software
| Graphical Email Clients | |
|---|---|
| Thunderbird | Popular free, cross-platform e-mail, RSS and newsgroup client |
| Kmail | Email component of Kontact |
| Sylpheed | Simple, lightweight client |
| Mailspring | New version of Nylas Mail |
| Claws Mail | Lightweight yet powerful and full-featured client |
| Evolution | Provides integrated mail, addressbook and calendaring functionality |
| Geary | Mail client for GNOME written in Vala |
| Astroid | Lightweight and fast Mail User Agent |
| Balsa | Email client for GNOME |
| Also known as Pantheon Mail | |
| Dodo | Based on the command line email swiss-army-knife notmuch |
| Aerion | Standalone lightweight e-mail client inspired by Geary |
Read our verdict in the software roundup.
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