| gmime3 | | Library for the creation and parsing of MIME messages (API v3) |
| gnarwl | | LDAP based mail autoresponder |
| GNUMail | | GNUstep clone of NeXT's Mail.app application |
| GNUMail-pgp (V) | | Bundle for PGP support in GNUMail |
| greetdelay | | Introduces a small delay before an SMTP greeting |
| grepmail | | Search utility for mbox formatted files |
| greylisting-spp | | Plugin for qmail-spp that provides greylisting |
| gyb | | Command line tool for backing up Gmail |
| heirloom-mailx | | BSD mail utility with MIME extensions |
| himalaya | | Command-line interface for email management |
| hs-email-validate | | Email address validation |
| hs-mbox | | Read and write standard mailbox files |
| hypermail | | Creates indexed, threaded HTML archives of email |
| ifile | | Intelligent mail filtering system |
| ilohamail (V) | | Light weight yet full featured multilingual webmail |
| im | | E-Mail and NetNews user interface commands |
| imap-uw | | University of Washington's IMAP, POP2, and POP3 servers |
| imap-uw-utils | | UW IMAP mailbox utilities |
| imapfilter | | Mail filtering utility for the IMAP |
| ImapGoose (V) | | Keep local Maildir directories synchronised with an IMAP server |
| imapproxy | | Simple connection caching IMAP proxy daemon |
| imapsync | | Incremental recursive IMAP transfer tool |
| imp | | Internet Messaging Program |
| incm | | Tool to get mail from mbox file or maildir |
| ingo | | Horde based generic and complete mail filter rule frontend |
| isync | | Synchronize a maildir with an imap server |
| ja-mh | | Rand MH mail handling system + Japanese patches |
| jchkmail | | Behavior-based virus and spam milter for Sendmail |
| kimap | | Job-based API for interacting with IMAP server |
| kmail | | KDE mail client |
| kmail-account-wizard | | KMail account wizard |
| kmailtransport | | Mail Transport Service |
| kmbox | | Library for accessing mail storages in MBox format |
| kmime | | Library for handling mail messages and newsgroup articles |
| ksmtp | | Job-based library to send email through an SMTP server |
| ktnef | | API for handling TNEF data |
| libdkim | | Portable library that signs and verifies emails |
| libesmtp | | Library to manage posting of electronic mail |
| libetpan | | Really nice mail library |
| libksieve | | KDE PIM library for managing sieves |
| libmilter | | Mail filter support library for sendmail |
| libsieve | | Library for parsing, sorting and filtering mail |
| libspf2 | | Implementation of the Sender Policy Framework |
| libsrs2 | | Implementation of the Sender Rewriting Scheme for SMTP forwarding |
| libsylph | | E-Mail client library |
| libytnef | | Yerase's TNEF Stream Reader library |
| mailagent | | Sophisticated automatic mail-processing tool |
| mailcommon | | KDE PIM library providing support for mail applications |
| mailcrypt | | Emacs frontend for PGP and GPG |
| maildrop | | Courier mail delivery agent with filtering abilities |
| mailfront | | Mail server network protocol front-ends |
| mailgraph | | RRDtool frontend for mail statistics |
| mailhops | | Shows the route of an Internet mail message |
| mailimporter | | Mail importer library |
| mailman | | The GNU Mailing List Manager |
| mailman2-python3 | | The GNU Mailing List Manager |
| mailman3 | | GNU mailing list manager |
| mailsend | | Utility to send mail via SMTP from command line |
| mailserv | | WWW interface to several types of mailing list servers |
| mailsort | | Sort mbox mail folders by date |
| mailsync | | Mailsync is a way of synchronizing a collection of mailboxes |
| mailutils | | Utilities, daemons, and filters for processing e-mail |
| mailwrapper | | Wrapper to support arbitrary Mail Transport Agents |
| mairix | | Program for indexing and searching email messages |
| majordomo | | The Majordomo mailing list manager |
| mb2md | | Converts one or more mboxes to maildirs |
| mblaze | | Set of Maildir utilities |
| mbox-importer | | Import mbox files to KMail |
| mdfrm | | Print a summary of mail in a Maildir waiting to be read |
| meli | | Terminal mail client |
| mess822 | | Library for parsing Internet mail messages |
| metamail | | Implementation of MIME, the Multipurpose Internet Mail Extensions |
| mew | | Messaging in the Emacs World |
| mhonarc | | Mailbox to HTML converter, suitable for list archives |
| mhpgp | | MH scripts to assist PGP operations on emails |
| milter-greylist | | Easy-to-use greylist milter for Sendmail and Postfix |
| milter-manager | | Milter to use milters effectively |
| milter-regex | | Milter enabling regular expression filtering |
| mime-construct | | Constructs and emails MIME messages |
| mimedefang | | To inspect/modify e-mail as it passes through your mail relay |
| mimp | | Internet Messaging Program for mobile devices |
| mini_sendmail | | Accept email on behalf of the real sendmail without spooling |
| minimalist | | Minimalistic Mailing Lists Manager |
| mlmmj | | Mailing list management made joyful |
| mm | | UNIX reimplementation of the TOPS-20 MM program |
| mopher | | Versatile mail filter |
| mpack (V) | | External MIME packer/unpacker |
| mpop | | Small, fast and portable POP3 client |
| msmtp | | SMTP client for MUAs |
| mu | | E-mail searching and indexing tools |
| mush | | Text-based mail client |
| mutt | | Text-based MIME mail client with PGP & S/MIME support |
| mutt-vid | | Manage multiple sender accounts in mutt |
| neomutt | | Fork of mutt with integrated community patches |
| netbiff | | Xbiff-like mail notification, handles multiple mailboxes |
| newmail | | Program to check multiple local mailboxes for new mail |
| newspipe | | Read RSS/Atom feeds as email messages |
| nmh | | Cleaned up MH mailer suite |
| nmzmail | | Fast mail searching for mutt |
| nopop3d | | POP3 server for when you don't want mail |