Thunderbird Alternatives for Windows

There are many alternatives to Thunderbird for Windows if you are looking for a replacement. The best Windows alternative is Claws Mail, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to Thunderbird and many of them are available for Windows so hopefully you can find a suitable replacement. Other interesting Windows alternatives to Thunderbird are SeaMonkey, Betterbird, Mailbird and eM Client.

filter to find the best alternatives

Thunderbird alternatives are mainly Email Clients but may also be Calendar Apps or Web Browsers.  Filter by these or use the filter bar below if you want a narrower list of alternatives or looking for a specific functionality of Thunderbird.
Thunderbird iconThunderbird
  2425
  • ...

Cross-platform email client providing POP/IMAP support, robust filtering, multiple accounts, and chat. Extendable via add-ons with RSS/Atom, etc.

More about Thunderbird
Thunderbird alternatives page was last updated Mar 5, 2025
  1. Claws Mail icon
     101 likes

    Claws Mail is an email client (and news reader), based on GTK+, featuring

    Quick response Graceful, and sophisticated interface Easy configuration, intuitive operation Abundant features Extensibility Robustness and stability.

    77 Claws Mail alternatives
    The main window

    License model

    • FreeOpen Source

    Application types

    Platforms

    • Windows
    • Linux
    • BSD

    Properties

    1.  Lightweight
    2.  Privacy focused

    Features

    1.  Extensible by Plugins/Extensions
    2.  Multiple Account support
    3.  IMAP Support
    4.  Spam Filter
    5.  Works Offline
    6.  No registration required
    7.  Ad-free
    8.  Dark Mode
    9.  Calendar Integration
    10.  Portable
    11.  GPG Encryption
    12.  Built-in RSS reader
    Claws Mail iconThunderbird Icon

    Claws Mail VS Thunderbird

    Is Claws Mail a good alternative to Thunderbird?
     
    Comments about Claws Mail as an Alternative to Thunderbird
     
       
    Jonathan DUMONT

    Despite the style, Claws is super fast and allow you to programs it with Perl and Python which is great for marketing automation.

    Top positive commentAug 1, 2019
    9
    Guest

    No HTML compose is the only reason I don't switch to it. We're not in 1980 anymore.

    Top negative commentSep 28, 2018
    18
    SViN

    I think most people are using gmail accounts or outlook accounts to access their emails. Claws supports Oauth2 to access said accounts but the implementation, is a complete PAIN.

    I can only realistically recommend something like this if your email provider is not forcing Oauth2.

    I would like for the devs to get to work into making the experience of setting up an account with oauth as painless as thunderbird.

    CommentSep 20, 2023
    1
    Show more comments
    3 of 8 comments
    Thunderbird Icon
    Claws Mail icon
    • Most users think Claws Mail is a great Thunderbird alternative.

    • Claws Mail is the most popular Windows & Linux alternative to Thunderbird.

    • Claws Mail is Free and Open SourceThunderbird is also Free and Open Source
    • Claws Mail is Lightweight and Privacy focusedThunderbird is not according to our users
  2. SeaMonkey icon
     235 likes

    Web-browser, advanced e-mail, newsgroup and feed client, IRC chat, and HTML editing in one application. Itis built on the open source Mozilla Gecko engine, the same code which underlies Thunderbird and is the base for the Firefox browser.

    180 SeaMonkey alternatives
    SeaMonkey screenshot 1

    License model

    • FreeOpen Source

    Application types

    Platforms

    • Mac
    • Windows
    • Linux
    • BSD
    • PortableApps.com

    Properties

    1.  Lightweight
    2.  Privacy focused

    Features

    1.  Integrated Email Client
    2.  Built-in RSS reader
    3.  Add-ons
    4.  Built-in Download Manager
    5.  WYSIWYG Support
    6.  Extensible by Plugins/Extensions
    7.  Portable
    8.  Ad-free
    9.  Support for Firefox extensions
    10.  Modular System
    SeaMonkey iconThunderbird Icon

    SeaMonkey VS Thunderbird

    Is SeaMonkey a good alternative to Thunderbird?
     
    Comments about SeaMonkey as an Alternative to Thunderbird
     
       
    Guest

    SeaMonkey is both a WEB BROWSER and EMAIL CLIENT. It's the successor of Mozilla Application Suite or Netscape Communicator, resp. Further it includes also a news client program, an HTML editor (SeaMonkey Composer) and an IRC client (ChatZilla).

    Positive commentNov 16, 2017
    21
    apostolfaliagas

    It has all of Thunderbird's features and many more.

    Positive commentFeb 19, 2018
    15
    Guest

    Unfortunately doesn't support synchronization with CardDAV address books.

    Negative commentMar 28, 2022
    0
    Show more comments
    3 of 4 comments
    Thunderbird Icon
    SeaMonkey icon
    • Some users think SeaMonkey is a great Thunderbird alternative, some don't.

    • SeaMonkey is the most popular Mac alternative to Thunderbird.

    • SeaMonkey is Free and Open SourceThunderbird is also Free and Open Source
    • SeaMonkey is Lightweight and Privacy focusedThunderbird is not according to our users
  3. Betterbird icon
     44 likes

    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.

    27 Betterbird alternatives
    Betterbird screenshot 1

    License model

    • FreeOpen Source

    Application types

    Platforms

    • Mac
    • Windows
    • Linux
    • Flathub
    • Chocolatey

    Properties

    1.  Privacy focused
    2.  Support for Themes
    3.  Lightweight

    Features

    1.  Multiple Account support
    2.  Extensible by Plugins/Extensions
    3.  Works Offline
    4.  Unified inbox
    5.  Ad-free
    6.  Portable
    7.  No Tracking
    8.  Spam Filter
    9.  Calendar Integration
    10.  SMTP Support
    11.  IMAP Support
    12.  POP3 Support
    Betterbird iconThunderbird Icon

    Betterbird VS Thunderbird

    Is Betterbird a good alternative to Thunderbird?
     
    Comments about Betterbird as an Alternative to Thunderbird
     
       
    Sam Lander

    Betterbird does everything that Thunderbird does (it's a soft fork), while improving bugs and features.

    Because it's a soft fork, it retains the security implementations of Thunderbird.

    Thunderbird actually implements many of the bug fixes created by Betterbird, but at a much slower pace.

    Top positive commentMay 31, 2023
    3
    drummer_nrg

    Betterbird is actively updated by a previous Thunderbird developer and is a fully compatible fork of Thunderbird which fixes some outstanding bugs. My add-ons like keepassxc-mail work fine!

    Positive commentMar 5, 2025
    1
    Guest

    It has many fixes for long existing bugs

    Positive commentJun 20, 2024
    2
    Show more comments
    3 of 5 comments
    Thunderbird Icon
    Betterbird icon
    • Almost everyone thinks Betterbird is a great Thunderbird alternative.

    • Betterbird is Free and Open SourceThunderbird is also Free and Open Source
    • Betterbird is Privacy focused and LightweightThunderbird is not according to our users
  4. Mailbird icon
     305 likes

    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.

    63 Mailbird alternatives
    Mailbird screenshot 1

    License model

    • FreemiumProprietary

    Application type

    Platforms

    • Mac
    • Windows

    Properties

    1.  Clean design

    Features

    1.  Sync Contacts
    2.  Dark Mode
    3.  Undo send
    4.  Email tracking
    5.  Unified inbox
    6.  GSuite Integration
    7. Slack icon  Slack integration
    8.  Multiple Account support
    9. Asana icon  Asana integration
    10.  Email template editor
    11.  Email Organizer
    12.  Spam Filter
    Mailbird iconThunderbird Icon

    Mailbird VS Thunderbird

    Is Mailbird a good alternative to Thunderbird?
     
    Comments about Mailbird as an Alternative to Thunderbird
     
       
    Guest

    Mailbird is missing most of the features which Thunderbird offers, like encryption and plugins

    Negative commentJan 2, 2016
    11
    Ian James

    Clean interface, much faster than Thunderbird. One touch unsubcribe is a nice touch and adding new accounts is a breeze

    Positive commentJun 2, 2021
    0
    Guest

    Great design. Great features

    Positive commentApr 21, 2021
    0
    Show more comments
    3 of 4 comments
    Thunderbird Icon
    Mailbird icon
    • Some users think Mailbird is a great Thunderbird alternative, some don't.

    • Mailbird is Freemium and ProprietaryThunderbird is Free and Open Source
  5. eM Client icon
     227 likes

    Looking for a full-featured email client with a modern and easy-to-use interface? Look no further than eM Client. Rated 3 out of 5, eM Client is a popular alternative to Thunderbird, offering all the features you need to manage your email, calendar, tasks, contacts, notes, and chat all in one place.

    With s...

    62 eM Client alternatives
    eM Client: Inbox view

    License model

    • FreemiumProprietary

    Application types

    Platforms

    • Mac
    • Windows
    • Android

    Top eM Client Features

    1.  IMAP Support
    2.  Calendar Integration
    3.  Multiple Account support
    4.  PGP Encryption
    5.  Dark Mode
    6.  Exchange
    7.  Unified inbox
    8.  Cloud Sync
    9.  Email Organizer
    10. Google Calendar icon  Sync with Google Calendar
    11.  Automatic Backup
    12.  CardDAV Support
    eM Client iconThunderbird Icon

    eM Client VS Thunderbird

    Is eM Client a good alternative to Thunderbird?
     
    Comments about eM Client as an Alternative to Thunderbird
     
       
    Comment summary: eM Client presents a clean interface with more built-in functions than Thunderbird, making it appealing for Mac and Windows users who prioritize design. However, users criticize it for being closed source, not supporting Linux, and having limited free accounts. Concerns include slow email rendering and potential phishing risks detected by antivirus software. Thunderbird remains favored for advanced configurability while eM Client is considered a viable alternative if users don't mind these limitations.
    3psilon

    A good Windows alternative if you use 1-2 mailboxes or don't mind paying.

    Top positive commentSep 3, 2017
    2
    LinuxDoge

    doesnt support Linux, isnt open source, not configurable enough

    Top negative commentMar 24, 2022
    1
    I am spezticle

    After installing I got malwarebytes and AVG antivirus alerts containing threats of phishing with urls such as "http://walmartsurvys.us/apple-touch-icon-precomposed.png" by way of the eM Client executable "MailClient.exe" There was a dozen more of them

    Do not install this phishing trash

    Negative commentJan 16, 2023
    1
    Show more comments
    3 of 12 comments
    Thunderbird Icon
    eM Client icon
    • Most users think eM Client is a great Thunderbird alternative.

    • eM Client is Freemium and ProprietaryThunderbird is Free and Open Source
  6. Mailspring icon
     106 likes

    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.

    41 Mailspring alternatives
    Clean design with integrated search and swipe gestures

    License model

    • FreemiumOpen Source

    Platforms

    • Mac
    • Windows
    • Linux
    • Arch Linux
    • Fedora
    • Ubuntu

    Properties

    1.  Support for Themes
    2.  Customizable

    Features

    1.  Unified inbox
    2.  Multiple Account support
    3.  Dark Mode
    4.  Email tracking
    5.  Snooze Mail
    6.  Ad-free
    7.  Theme Customization
    8.  Built-in translation
    9.  Email Organizer
    10.  Built-in themes
    11.  Extensible by Plugins/Extensions
    12.  Auto Update
    Mailspring iconThunderbird Icon

    Mailspring VS Thunderbird

    Is Mailspring a good alternative to Thunderbird?
     
    Comments about Mailspring as an Alternative to Thunderbird
     
       
    3psilon

    Great alternative, especially for casual users. Simple, streamlined UI, feels fresh.

    Top positive commentMay 2, 2018
    1
    Guest

    Need to create an account on a third-party company to access your email.

    Top negative commentSep 28, 2018
    59
    Matt Schaefer

    Unable to even find an address book or ability to import a csv file from previous mail client. You lose me when things are made so "modern-clean" that I have to consult a manual or Google things.

    Negative commentJul 15, 2022
    0
    Show more comments
    3 of 7 comments
    Thunderbird Icon
    Mailspring icon
    • Most users think Mailspring is a great Thunderbird alternative.

    • Mailspring is Freemium and Open SourceThunderbird is Free and Open Source
    • Mailspring is CustomizableThunderbird is not according to our users
  7. Spark Mail icon
     125 likes

    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.

    62 Spark Mail alternatives
    Spark Mail screenshot 1

    License model

    • FreemiumProprietary

    Application types

    Platforms

    • Mac
    • Windows
    • Android
    • iPhone
    • iPad
    • Apple Watch

    Top Spark Mail Features

    1.  Multiple Account support
    2.  Email Scheduling
    3.  Snooze Mail
    4.  Cloud Sync
    5.  Calendar Integration
    6.  Dark Mode
    7.  Email Organizer
    8.  Unified inbox
    9.  Works Offline
    10.  Mail Filtering
    11.  Ad-free
    12. Google Calendar icon  Sync with Google Calendar
    Spark Mail iconThunderbird Icon

    Spark Mail VS Thunderbird

    Is Spark Mail a good alternative to Thunderbird?
     
    Comments about Spark Mail as an Alternative to Thunderbird
     
    folkomaton

    Free, simple, reliable, easy to manage multiple accounts, fair amount of customization, synchronisation, templates

    Positive commentApr 24, 2020
    0
    rmpbklyn

    no sorting, dont show allmail for gmail

    Negative commentJun 10, 2018
    -3
    Thunderbird Icon
    Spark Mail icon
    • Most users think Spark Mail is a great Thunderbird alternative.

    • Spark Mail is Freemium and ProprietaryThunderbird is Free and Open Source
7 of 46 Thunderbird alternatives