The best alternative to Microsoft Outlook is Betterbird, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Microsoft Outlook and many of them are so hopefully you can find a suitable replacement. Other interesting alternatives to Microsoft Outlook are FairEmail, eM Client, Pelton and EssentialPIM.
Betterbird, a soft fork of Mozilla Thunderbird, improves user experience with advanced features, bug fixes, security patches, and multi-row descriptions similar to Outlook. Compatible with multiple platforms and can be used alongside Thunderbird, sharing the same profile.
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Open-source, privacy-focused email client offering features such as encryption via OpenPGP and S/MIME, unlimited accounts, a unified inbox, customizable settings, and reformatted emails to prevent phishing. Supports two-way synchronization and provides Pro features for additional customization.
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eM Client is a full featured e-mail client with a modern and easy to use interface. eM Client also offers calendar, tasks, contacts, notes and chat.
CzechiaEU
Free, open-source client for Windows, macOS, and Linux, offering local email storage and search online or offline, privacy-focused with no telemetry or third-party servers, IMAP and SMTP support, intuitive interface, and multiple account support.
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The powerful, full-featured Personal Information Manager for Windows offering Email, Synchronization, Portability, Network support, Android and iOS versions.
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KMail is the email component of Kontact, the integrated personal information manager of KDE. Kontact is a personal information manager and groupware software suite for KDE. It supports calendars, contacts, notes, to-do lists, news, and email.
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Engineered for iOS, macOS, and watchOS, this fast mail client supports multiple account types, custom actions, Smart Inbox filtering, unified inbox, privacy mode, email scheduling, snooze, third-party app integration, flexible personalization, and advanced workflow tools.
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Amie is a productivity application that facilitates task, event, and contact management, integrating a scheduling feature for task and event time allocation, and effectively transforming the calendar into a todo list, with color-coding for improved organization and visual...
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No-frills, easy to use, easy to maintain Email client for Android based on the JSON Meta Application Protocol (JMAP).
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The open source cloud with LibreOffice online - LibreOffice online + Seafile + KDE. Improve your productivity and communicate better with your team members. The world is moving forward. Welcome to the open source cloud!.
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