--- title: Claws Mail canonical: https://saasranked.com/software/claws-mail/ category: Email Clients points: 61 rank: 8 of 10 facts_checked: 2026-10-08 --- # Claws Mail Lightweight open-source mail client with IMAP, POP3 and GnuPG, free for Windows and Linux. 61 points out of 100. #8 of 10 email clients. Vendor: Claws Mail project. Website: https://www.claws-mail.org/ - The download page shows no price, and the app is released under the GPL [1][3]. - Version 4.4.0 came out on 9 March 2026, with 32-bit and 64-bit Windows installers [3][4]. - It handles IMAP and POP3, and OAuth2 for Gmail and Microsoft accounts [2][6]. - Filters run on incoming mail when you turn that option on for the account [8]. - GnuPG is supported, and PGP and S/MIME plugins come with the Windows download [2][4]. Verdict: Claws Mail suits people who want a free, light client with filters, templates, GnuPG and S/MIME [2][4][8]. The catch: Gmail and Microsoft sign-in needs you to register your own app first, Exchange works only through IMAP, and the pages show no unified inbox or delayed send, with a calendar only through a plugin [2][5][6][7]. Best for: People who want a small, keyboard-friendly client with strong filtering and PGP. ## Points | Criterion | Line | Value | Points | Note | |---|---|---|---|---| | Mail and accounts | Account types | IMAP, POP3, Gmail and Microsoft 365 sign-in | 9/12 | IMAP and POP3 [2]; OAuth2 for Gmail and Microsoft [6]; Exchange only through IMAP, no EWS or Graph [7]. | | Mail and accounts | Unified inbox | Not published | 0/4 | Not published on the vendor's features page or interface FAQ [2][11]. | | Mail and accounts | Mail tools | Templates | 2/8 | Features page lists templates, message queueing and drafting; no scheduled send, snooze or undo send [2]. | | Mail and accounts | Filters and rules | Yes | 3/3 | Filtering rules can run when mail is received, if the account option is on [8][2]. | | Calendar and contacts | Built-in calendar | Not published | 0/6 | Plugins page mentions a personal calendar but not a calendar view or creating events [5]. | | Calendar and contacts | CalDAV and CardDAV | Not published | 0/3 | Plugins page lists webCal subscriptions; CalDAV and CardDAV are not mentioned [5][2]. | | Privacy and encryption | OpenPGP | Yes | 7/7 | Features page lists GnuPG support; plugins page lists PGP/Inline and PGP/MIME plugins [2][5]. | | Privacy and encryption | S/MIME | Yes | 6/6 | Windows page says the S/MIME plugin is integrated with the main download; FAQ shows setup with your own certificate [4][5][9]. | | Privacy and encryption | Blocks tracking pixels | Not published | 0/4 | Features page lists configurable image display; the default is not stated [2][11]. | | Privacy and encryption | Open-source apps | Yes | 6/6 | Home page says Claws Mail is distributed under the GPL [1]. | | Privacy and encryption | Mail stays on your device | Not published | 0/5 | FAQ says mail is stored in a local folder; no page states it avoids vendor servers [10]. | | Systems and upkeep | Other systems | Linux | 2/10 | Downloads page lists Linux packages and BSD ports; no macOS, iOS, Android or web version [3]. | | Systems and upkeep | Released in the last year | Yes | 5/5 | Version 4.4.0 released 9 March 2026; Windows 4.4.0-1 installers are listed [3][4]. | | Price | No ads in the app | Yes | 3/3 | Open-source app under the GPL [1]. | | Price | Free plan | Yes | 6/6 | GPL software offered as a download with no price shown. Read as free [1][3]. | | Price | Cost of a year | $0 | 12/12 | No price is charged on the vendor's pages; the full app is a free download [3]. | ## Plans | Plan | Price | Per month (USD) | |---|---|---| | Free | Free [1][3] | $0 | ## Strengths - Free to download, released under the GPL [1][3]. - Has filtering, templates and GnuPG support, and the PGP and S/MIME plugins come with the Windows download [2][4][5]. - The Windows installers for 4.4.0 are 32-bit and 64-bit [4]. - Filters can run when mail arrives or by hand on a folder [8]. ## Limits - OAuth2 for Gmail and Microsoft needs you to create your own Google Cloud or Microsoft Entra app [6]. - Exchange is reached only through IMAP; the FAQ says MAPI is not supported [7]. - A calendar is limited to a plugin that handles vCalendar messages and webCal subscriptions [5]. - No Mac, iOS, Android or web app is listed on the download page [3]. - The features page lists no scheduled send, snooze or undo send [2]. ## Sources 1. [Claws Mail](https://www.claws-mail.org/), Claws Mail project, accessed 2026-10-08 2. [Claws Mail features](https://www.claws-mail.org/features.php), Claws Mail project, accessed 2026-10-08 3. [Claws Mail downloads](https://www.claws-mail.org/downloads.php), Claws Mail project, accessed 2026-10-08 4. [Claws Mail for Windows](https://www.claws-mail.org/win32/), Claws Mail project, accessed 2026-10-08 5. [Claws Mail plugins](https://www.claws-mail.org/plugins.php), Claws Mail project, accessed 2026-10-08 6. [Oauth2 (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/Oauth2), Claws Mail project, accessed 2026-10-08 7. [Connecting to MS Exchange (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/Connecting_to_MS_Exchange), Claws Mail project, accessed 2026-10-08 8. [Filtering and Processing of Messages (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/Filtering_and_Processing_of_Messages), Claws Mail project, accessed 2026-10-08 9. [S/MIME howto (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/S/MIME_howto), Claws Mail project, accessed 2026-10-08 10. [General Information (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/General_Information), Claws Mail project, accessed 2026-10-08 11. [Interface (Claws Mail FAQ)](https://www.claws-mail.org/faq/index.php/Interface), Claws Mail project, accessed 2026-10-08