The best open source alternative to Apple Mail is Macro Mail. If that doesn't suit you, we've compiled a ranked list of other open source Apple Mail alternatives to help you find a suitable replacement. Other interesting open source alternatives to Apple Mail are: Mailspring, Tuta, and Twake Mail.
Apple Mail alternatives are mainly Email Clients but may also be AI Personal Assistants or Encrypted Communication Tools. Browse these if you want a narrower list of alternatives or looking for a specific functionality of Apple Mail.
An AI-powered email client that combines inbox management, chat, tasks, and AI agents in one shared workspace, built for keyboard-driven workflows.

Macro Mail is an email client built around the opinion that your inbox shouldn't be separate from your tasks, conversations, and AI tools. Unlike Superhuman, It pulls email, chat, tasks, and AI agents into a single shared workspace while still being designed for people who spend a significant chunk of their day in their inbox and want to move fast.
The keyboard-first design is central to how it works. You can navigate, triage, and act on messages without touching the mouse, which adds up over a full workday.
Key capabilities include:
Macro Mail is aimed at professionals and teams who find standard email clients too passive. If you're already using tools like Inbox Zero for triage or exploring AI agent-based email handling, Macro Mail positions itself as an all-in-one alternative that keeps everything in one place.
The AI layer is woven into drafting, summarization, and agent actions throughout the product. That makes it a different category from clients that add AI as a plugin or optional add-on.
Desktop email client for Mac, Windows, and Linux with unified inbox, read receipts, link tracking, send later, grammar checking, and contact enrichment.

Mailspring is a native desktop email client for Mac, Windows, and Linux, built for people who send a lot of email and want more than basic send-and-receive. It connects to Gmail, iCloud, Office 365, Fastmail, Yahoo, and any IMAP/SMTP provider, pulling everything into a single unified inbox.
The free tier covers most daily needs: multi-account support, advanced search across all accounts, undo send, grammar and spell checking (powered by LanguageTool), custom signatures, dark mode, and localization into 12 languages with right-to-left layout support for Hebrew and Arabic. It also translates incoming and outgoing messages between English, Spanish, French, German, Russian, and simplified Chinese directly inside the composer.
Mailspring Pro ($8/month) adds the features that matter for professional communication:
Under the hood, Mailspring uses a native C++ sync engine rather than wrapping a browser, which keeps RAM usage roughly half that of comparable clients and launch time under a second. Email syncs directly via IMAP, CalDAV, and CardDAV, so your messages go from your mail provider to your machine without passing through Mailspring's servers.
Compared to something like Spark Mail or Mailbird, Mailspring's main differentiators are its open codebase, direct sync architecture, and the combination of tracking features with a genuinely fast native interface. It runs on Linux including ARM64 and Wayland, which few desktop email clients bother to support properly.
Over 800,000 users have downloaded it since launch, and it's maintained by a small independent team with no outside investors.
Tuta offers encrypted email, calendar and contacts with quantum-resistant security, protecting your privacy without ads or tracking.

Tuta is a secure communication platform that provides end-to-end encrypted email, calendar, and contacts.
Key features:
Tuta uses renewable energy to power its services, demonstrating a commitment to sustainability. The platform is trusted by thousands of businesses, including financial institutions and human rights organizations, to safeguard sensitive communications.
With Tuta, you can take back control of your data and enjoy private, secure communication without compromising on features or ease of use. Whether for personal or business use, Tuta provides a comprehensive solution for those who value their digital privacy and security.
Open source professional email solution with PGP encryption, JMAP protocol, AI-powered responses, and advanced antispam protection. Control your data privately.

Twake Mail is a next-generation open source email solution that prioritizes security, privacy, and performance for professional use. Built on the cutting-edge JMAP protocol, it delivers 30 times better efficiency than traditional IMAP systems while providing enterprise-grade security features.
Key Security Features:
Modern Technology Stack:
Enterprise Benefits:
Advanced Search & Organization:
Developed by LINAGORA, a leader in European open source with 24 years of experience, Twake Mail is backed by active participation in IETF standardization and Apache Foundation projects. The solution offers complete transparency with code available on GitHub for review and contribution.
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