The best free alternative to Microsoft Outlook is Thunderbird, which is also Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Microsoft Outlook and loads of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to Microsoft Outlook are K-9 Mail, Evolution, eM Client and Mailbird.
Streamline your email experience by managing multiple accounts, integrating apps like Slack and Google Calendar, and using AI-driven features like drafting and spam prevention. Customize your workspace with themes, notifications, and tools for improved productivity and a modern interface.
Cross-platform email client supporting multiple identities, chat, and strong filtering. Extend functionality with add-ons like RSS/Atom feed readers and PGP support.
The interface is just impossible for many people to use.
I remember when I first used Thunderbird, many years ago, as I'd rather have a single interface for productivity. But the interface through me off and I never got on with the editor. Coming back to it now, it's fresher and smoother. Absolutely love it. In my opinion this is the only true alternative to Outlook. Then there's the bonus of extensions to further enhance it. Though, I'd like to see further improvements to the calendar integration.
K-9 is an open source email client for Android with multi-folder sync, email signatures, Bcc-to-self, return-address configuration, keyboard shortcuts, Exchange Support, message flagging, IMAP deletes, saving attachments, configurable notifications and more.
Not the prettiest, but it's open source (trustworthy), free, privacy-respecting and very functional. My go-to Android email client. I cannot hesitate less in recommending it.
Deletes e-mail from the server even when underground in NYC subway. Makes life so easy to delete e-mails while on the train When surfacing, K-9 syncs with the server and POOF....those unwanted e-mails are gone from the server.
Evolution is a personal information management application that provides integrated mail, calendaring, address book and task list functionality.
It runs on Linux and you still have content if you are offline.
I can just find everything instantly, Outlook I'm having to go to Chat GPT to research where the option is hidden!
This would be the best alternative, except that it requires the Gnome desktop, so users of other desktop environments need to look elsewhere.
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.
It is not very overcomplicated! Very simple, but functional design. therefore also very easy to set up and use.
Supports 365 Shared Mailboxes.
One of the only fully integrated email and calendar solutions that supports Office365, Exchange, Outlook, Gmail, GSuite, POP, and IMAP. Good performance and usability.
Streamline your email experience by managing multiple accounts, integrating apps like Slack and Google Calendar, and using AI-driven features like drafting and spam prevention. Customize your workspace with themes, notifications, and tools for improved productivity and a modern interface.
Not enough functionality. No smart attachment feature, no quick sort by address or flags or attachments etc. Not really a business email client
These are email clients not replacements for outlook
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.
E-mail app with all the great features: swipes (long/short), snooze, add (multiple) attachments from the cloud, support for various e-mail services and more.
Nice client. Great UI. It does lack Caldav support unfortunately.
Boost your productivity and send better email with Mailspring, a beautiful, fast email client for Mac, Windows, and Linux. Mailspring is free to use and an optional pro version adds read receipts, send later, reminders and more.
Since Thunderbird is still bloated and overcomplicated for me on Linux, I'm using Mailspring for the moment. It's good, the interface is nice and it has plenty of features.
Beautiful theme options with custom designed themes available. I tried thunderbird a few times but always came back to mailspring. I LOVE the "views" feature that shows you how many times an email was opened and if it was forwarded by the recipient!
Speed of work, good connection to the mail server, speed search.
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.
open source, secure, regularly updated
Access, view and manage messages from all your email accounts in one place. Categorize your messages into easy to browse categories. Catch up on email easily with Apple Intelligence powered Priority Messages and summarizations.
Lots of limitations a la Apple's usual attempts to protect users from themselves. E.g. you can choose one default send-from address, or let Mail choose, and the choices it makes are useless. You can't just click on one of your mailboxes, create a new email, and have it always send from the mailbox you chose. Also no way to turn off in-line attachments so you can attach files the way literally every other email client does.
Ease-of-use, simple setup, already installed
Outlook is an all-in-one solution including mail calendar etc. this soft does only one thing
Geary is an email application built around conversations, for the GNOME 3 desktop.
Beatiful frontend Stable working Advanced features
Email and news client on GTK+ foundation featuring quick performance, extensible plugins, secure protocols, advanced filtering, strong folder and contact management, lightweight design, powerful search, customizable interface, multi-language support, and encryption.
Claws Mail is email only, does not have many of the features of Outlook. Displaying HTML mail is sketchy at best.
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Despite its age, Thunderbird remains the most fully featured email client out there. Various add-ons can extend its functionality, it (now) has a built in calendar and, unlike Outlook, it's free, open source and respects your privacy.