| 1 |  Tuta MailTutanota is an email client with a strong focus on security and privacy that lets you encrypt emails on all your devices. | 362.261023.2 | Open source | October 23, 2026 | — | 50.1K ↓ |
| 2 |  MailspringBoost your productivity and send better email with Mailspring, the best mail client for Mac, Linux, and Windows. | 1.26.2 | Open source | October 22, 2026 | — | 7.7K ↓ |
| 3 |  Proton Mail BridgeUse Proton Mail with your desktop email client | 3.27.1 | Open source | October 8, 2026 | — | 26.2K ↓ |
| 4 |  eM ClientFast email client with full Gmail, Hotmail and other services synchronisation. Best replacement for MS Outlook or Thunderbird. Free version for Home users. | 11.0.1054 | Free | October 8, 2026 | 1.7 MB | 98.1K ↓ |
| 5 |  Proton MailKeep your conversations private with Proton Mail, an encrypted email service based in Switzerland. | 1.14.0 | Proprietary | September 9, 2026 | 139.1 MB | 7.1K ↓ |
| 6 |  MFCMapiProvides access to MAPI stores to facilitate investigation of Exchange and Outlook issues and to provide developers with a sample for MAPI development. | 26.0.26291.01 | Open source | October 19, 2026 | — | 5.7K ↓ |
| 7 |  Claws MailThe user-friendly, lightweight, and fast email client | 4.1.1-1 | Open source | December 8, 2022 | 34.2 MB | 11K ↓ |
| 8 |  Prospect MailUnofficial desktop client for Microsoft Outlook | 1.2.1 | Open source | April 1, 2026 | — | 592 ↓ |
| 9 |  BetterbirdBetterbird is a fork of Mozilla Thunderbird with additional features and bugfixes. | 153.5.0 | Open source | October 14, 2026 | — | 44.3K ↓ |
| 10 | MMozilla Thunderbird (en-US)Thunderbird is a free email application that is easy to set up and customize - and it's loaded with great features! | 158.0.1 | Open source | October 21, 2026 | — | — |
| 11 | PPostboxPostbox is the power email app for busy professionals, like you. | 7.0.56 | Proprietary | July 19, 2022 | — | 17.5K ↓ |
| 12 | BblatA Windows command line utility that sends eMail using SMTP or post to usenet using NNTP. | 3.2.24 | Open source | | — | 19.3K ↓ |
| 13 |  Zimbra DesktopZimbra Desktop is a desktop email client that synchronizes your emails even when offline, so your mailbox is updated when you go online. | 4.50.0 | Proprietary | September 24, 2026 | — | 9K ↓ |
| 14 | TtrojitaIMAP e-mail client with lightweight GUI | 0.7 | Open source | | — | 10.7K ↓ |
| 15 | WWinlink ExpressThe ultimate radio email client designed for seamless communication | 1.8.6.0 | Proprietary | September 28, 2026 | 50.4 MB | 2.5K ↓ |
| 16 |  MeruThe Gmail experience you deserve | 3.63.2 | Open source | October 9, 2026 | — | ★ 1K |
| 17 |  Gmail DesktopNifty Gmail desktop app | 2.25.3 | Open source | March 30, 2021 | — | ★ 1K |
| 18 |  matchaA beautiful and functional email client for your terminal. | 1.1.0 | Open source | October 15, 2026 | — | ★ 1.1K |
| 19 |  PebbleA local-first desktop email client for people who want a calmer, more private inbox. | 0.1.5 | Open source | September 9, 2026 | — | ★ 598 |
| 20 | HhimalayaMinimalist CLI email client, written in Rust | 2.2.1 | Open source | | — | 219 ↓ |
| 21 |  Markdown OutlookA simple plugin for Outlook 2013+ which adds a button to the compose mail menu to enable Markdown mode. When enabled your email will be turned from Markdown syntax to html when sending. | 1.0.0 | Open source | January 20, 2022 | — | ★ 425 |
| 22 | FFoxmailThe easy-to-use email management expert | 7.2.25.563 | Free | July 10, 2026 | 149.3 MB | — |
| 23 |  ProtonClientAn unofficial desktop client for ProtonMail done with electron nativefier | 1.2.3 | Open source | December 3, 2021 | — | ★ 80 |
| 24 | MMailbirdA powerful, intuitive, ultra-customizable and dead set on mailing | 3.0.63 | Proprietary | August 31, 2026 | — | — |
| 25 |  iGotA wechat, email, and app notifications desktop client. | 1.1.1 | Open source | March 30, 2021 | — | ★ 57 |
| 26 |  Outlook for Office365Outlook Web Application as a dedicated application. This hosts mail.office365.com and is suitable for using with enterprise work or school environments | 1.1.1.0 | Open source | June 13, 2021 | — | ★ 51 |
| 27 |  Outlook for Outlook.comOutlook Web Application as a dedicated application. This hosts outlook.com and is suitable for using for personal email. | 1.1.1.0 | Open source | June 13, 2021 | — | ★ 51 |
| 28 |  Loop Email (Beta)All-in-one Shared Inbox and Team Email Platform | 7.7.1-beta.2 | Proprietary | March 30, 2026 | — | ★ 4 |
| 29 |  Loop EmailAll-in-one Shared Inbox and Team Email Platform | 8.0.13 | Proprietary | September 28, 2026 | — | ★ 4 |
| 30 |  MailFathom CLIThe administrative command-line client for MailFathom, a self-hosted AI-native mail service. | 0.4.0 | Open source | September 1, 2026 | — | ★ 16 |
| 31 | SSpark DesktopSmart. Focused. Email. | 3.32.1 | Proprietary | October 23, 2026 | 227.8 MB | — |
| 32 | MMozilla Thunderbird ESR (en-US)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 33 | MMozilla Thunderbird ESR (af)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 34 | MMozilla Thunderbird ESR (ar)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 35 | MMozilla Thunderbird ESR (ast)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 20, 2026 | — | — |
| 36 | MMozilla Thunderbird ESR (be)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 20, 2026 | — | — |
| 37 | MMozilla Thunderbird ESR (bg)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 38 | MMozilla Thunderbird ESR (br)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 39 | MMozilla Thunderbird ESR (ca)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 40 | MMozilla Thunderbird ESR (cs)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 41 | MMozilla Thunderbird ESR (cy)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 20, 2026 | — | — |
| 42 | MMozilla Thunderbird ESR (da)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 20, 2026 | — | — |
| 43 | MMozilla Thunderbird ESR (de)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 44 | MMozilla Thunderbird ESR (dsb)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 45 | MMozilla Thunderbird ESR (el)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 46 | MMozilla Thunderbird ESR (en-CA)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 47 | MMozilla Thunderbird ESR (en-GB)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 48 | MMozilla Thunderbird ESR (es-AR)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 49 | MMozilla Thunderbird ESR (es-ES)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |
| 50 | MMozilla Thunderbird ESR (es-MX)The official annual extended support release of Thunderbird intended for users who want all available new features on an annual basis and stability/security fixes on a monthly basis. | 153.5.1 | Open source | October 21, 2026 | — | — |