Mail Account Setup Wizard

Prior to this feature you had to know your IMAP, SMTP, and SSL/TLS settings. Now all you need to provide is your name, email address, and password and the email account set up wizardry will check our database and find the email settings for you.

Personalized Email Addresses

Ever dreamed of having a personalized email address (such as "") for you, your family or your business? Thunderbird makes this easy - you can sign up for a new email address within Thunderbird, and it will all be set up automatically for you ready to send and receive.

One-click Address Book

One-click Address Book is a quick and easy way to add people to your address book. Add people by simply clicking on the star icon in the message you receive. Two clicks and you can add more details like a photo, birthday, and other contact information.

Attachment Reminder

The attachment reminder looks for the word attachment (and other words like file types) in the body of your message and reminds you to add an attachment before hitting send.

Multiple-channel chat

Enjoy real-time conversation with your contacts, right from your favorite messaging application, with multiple supported networks. Thunderbird makes it easy to search through both past conversations and received emails.

Tabbed Email

Thunderbird replicates the new look and feel of Mozilla Firefox in an effort to provide a similar user experience across all Mozilla software desktop or mobile and all platforms.

Tabbed email lets you load emails in separate tabs so you can quickly jump between them. Tabs appear on the top of the menu bar providing a powerful visual experience and allowing the toolbars to be much more contextual.

Tabbed email lets you keep multiple emails open for easy reference. Double-clicking or hitting Enter on a mail message will open that message in a new tab.

When quitting Thunderbird, visible tabs will be saved and will be restored when you open Thunderbird the next time. There is also a Tab menu on the Tab toolbar to help you switch between tabs.

Search the Web

You can now search the Web without having to leave Thunderbird. Type whatever comes to mind in Thunderbird’s search box and choose from several different search providers.

You can also highlight words in your email, right click, and select "search the web for:" to start your Web search.

Quick Filter Toolbar

The Quick Filter Toolbar lets you filter your email faster. Start typing in words in the Quick Filter search box and the results are displayed instantly. Or you can filter your email by New Messages, Tags, and people in your Address Book. You can also "Pin" or save a Filter and use it across multiple folders.

Search Tools

The search interface in Thunderbird contains filtering and timeline tools to pinpoint the exact email you’re looking for. Thunderbird also indexes all of your emails and chat conversations to help you search even faster. Your search results are displayed in a tab so you can easily switch back and forth to your search results and other email.

Message Archive

If you think you’re going to need an email in the future but want it out of your inbox without deleting it, archive it! Archiving helps you manage your inbox and put your email into the archive folder system.

Selecting the Archive button or hitting the ‘A’ key will archive your email.

Activity Manager

The Activity Manager records all the interactions between Thunderbird and your email provider in one place. There’s no more guess work. You only have to look in one place to see everything that’s happening with your email.

What's New:

Thunderbird version 91 is only offered as direct download from and not as an upgrade from Thunderbird version 78 or earlier. A future release will provide updates from earlier versions.


  • Native support for macOS devices built with Apple Silicon CPUs
  • New Thunderbird now operates in multi-process (e10s) mode by default
  • New Latvian language support
  • New user interface for adding attachments
  • New Enable redirect of messages
  • New Ability to change order of accounts in UI
  • New Allow showing empty CC/BCC rows in compose window
  • New Warning popup when sending a reply to a likely non-existant email address such as ""
  • New Warning popup when public recipients of a message exceeds threshold
  • New Add support for "X-Unsent: 1" header, to open a saved email in a compose window for editing
  • New Add support for non-ASCII characters in recipient addresses
  • New Context menu to expand mail list pills in the compose window to the list of recipients
  • New Quick Find is now available in the multi-message (thread summary) view
  • New Keyboard shortcuts to access To/CC/BCC fields of compose window
  • New Allow pinning folder views to the Folder Pane
  • New Language packs and dictionaries added to about:support
  • New PDF.js viewer now included in Thunderbird
  • New OpenPGP: "Copy Key Id" option added to Key Manager context menu
  • New OpenPGP: Added config option to disable encrypting saved drafts
  • New Encrypt mail to BCC recipients (with warning that it will expose the recipients in the list of keys)
  • New CardDAV address book support
  • New CardDAV address books automatically detected based on provided user information
  • New Access to Outlook Contacts; To enable, set ldap_2.servers.outlook.dirType to 3; This setting may cause startup delays.
  • New Suggest replacements for discontinued/incompatible add-ons
  • New Chat: Beta-level support for Matrix servers (set chat.prpls.prpl-matrix.disable to false)
  • New Calendar: Remote calendar auto-detection now supported
  • New Calendar: Calendar and category colors now displayed in selection dropdowns
  • New Calendar: "Edit" item added to event context menu
  • New Calendar: Support opening of .ics files by double-click
  • New Calendar: Thunderbird now informs the operating system that it knows how to open webcal: URLs
  • New Calendar: Filter and sort items to be imported in the Import dialog
  • New Prompt to choose the identity of an accepted calendar invite when no identity matches the event attendees list
  • New Support mid: URL scheme for Related Links in calendar event dialogs
  • New Permissions to access calendar and address book are now requested when a GMail account is set up, so that calendar and address book can be accessed without having to re-authorize (see notes)
  • New Calendar: Per-calendar and global notification settings (in addition to alerts set in events)
  • New Tasks: Undo/Redo support for event and task creation and deletion


  • Changed "Master Password" renamed to "Primary Password"
  • Changed Renamed "Add-ons" to "Add-ons and Themes" and "Options" to "Preferences"
  • Changed Account setup moved to a tab
  • Changed Mail recipients that are not found in any address book will no longer appear in red type; invalid addresses will appear red
  • Changed Clicking on an already-selected pill in the recipient list will now allow editing the address
  • Changed Folder pane color scheme overhauled with a focus on readability
  • Changed Sending backend, SMTP protocol, and LDAP protocol implementations rewritten in Javascript
  • Changed Sending backend, SMTP, and IMAP protocols now operate only in UTF-8 mode
  • Changed Sending a message will now fail if any recipients are not accepted by the SMTP server
  • Changed Error messages from an SMTP server are now displayed to the user
  • Changed UI Customization controls moved to the View menu
  • Changed End-to-End Encryption "Advanced Settings" are now disabled when encryption is not configured
  • Changed Movemail support removed
  • Changed WeTransfer FileLink provider removed
  • Changed Enterprise policies updated
  • Changed Printing UI updated
  • Changed AutoComplete from LDAP directories now searches by substring instead of left-side match
  • Changed Chat modules and custom widgets are now lazy-loaded to improve Thunderbird startup time
  • Changed Default IRC server for new chat accounts changed to ""
  • Changed Chat: Image based emoticons replaced with Unicode
  • Changed Calendar: Opening an existing event now opens summary dialog
  • Changed Calendar: Default to CalDAV when supported by the server


  • Thunderbird did not properly handle Self-signed certificates on IMAP servers
  • Fixed Various issues with special and non-ASCII characters in IMAP folders names, especially on Gmail
  • Fixed Drag & drop operations could be disrupted by incoming mail notifications
  • Fixed Dragging a folder from an authenticated IMAP server to a not-yet authenticated server fails
  • Fixed Temporary errors from POP3 servers would cause Thunderbird to stop downloading mail until it was restarted
  • Fixed Favorite Folder view did not maintain UI state between Thunderbird restarts
  • Fixed Saved search virtual folders were not retained after restarting Thunderbird
  • Fixed Thunderbird did not correctly warn about all affected filters when removing a folder
  • Fixed Manually running filters on a maildir folder did not work
  • Fixed Partially downloaded messages displayed in a stand-alone window did not refresh after clicking link to download the rest of the message
  • Fixed An erroneous "Sender" header was displayed in the message preview after viewing certain S/MIME signed emails
  • Fixed Some temporary files created by the message composer were not automatically removed after closing the compose window
  • Fixed Archiving messages from an NNTP account made the target folder unusable
  • Fixed Compose window: The user-configured style for quoted text was not honored
  • Fixed Message headers in compose window disregarded manual resizing when adding additional recipients
  • Fixed Various improvements to new message notifications
  • Fixed A Thunderbird icon pinned to the Windows taskbar reverted to a non-functional placeholder after an update
  • Fixed Various improvements to recipient pills in message compose window
  • Fixed Keyboard shortcut to open the Message Security popup did not work on Mac
  • Fixed Subject column in message lists sometimes showed text from invalid email headers
  • Fixed Account settings: When creating a new account, some already entered settings did not copy to the Advanced Config dialog
  • Fixed Default address book preference was not honored in the contacts sidebar
  • Fixed Import Address Book from CSV did not not allow mapping all available fields
  • Fixed LDAP address books did not display multi-valued attributes
  • Fixed Address Book: Users with LDAP admin rights could delete accounts if trying to delete an entry from an address book backed by LDAP
  • Fixed Some preferences related to an address book were not removed when the address book was deleted
  • Fixed Shortcut for Advanced Address Book Search (Ctrl+Shift+F) did not work on Linux
  • Fixed Radio buttons could not be selected on photo tab of an address card
  • Fixed Windows uninstaller did not always remove all Thunderbird program files
  • Fixed Chat: Double clicking an account type in new account wizard did not select it
  • Fixed Chat account settings did not always save as expected
  • Fixed User nickname colors were not used in chat content
  • Fixed Chat: Multiple system messages did not collapse
  • Fixed Calendar: Reminder details appeared editable when viewing an event
  • Fixed Calendar: HTML rendering in event descriptions restored
  • Fixed Calendar: The toolbar in the invitation details dialog was not honoring the theme colors
  • Fixed Calendar: Various dialog updates
  • Fixed Calendar: Import and export via CSV did not parse years correctly in event dates
  • Fixed Calendar: Event boxes were not always focused when clicked
  • Fixed Dragging and dropping an ICS file to the Today Pane did not populate the "New Event" dialog
  • Fixed Calendar: Reduced flickering effect in Today Pane
  • Fixed Calendar: The time of day indicator line did not update automatically
  • Fixed Location field was not preserved when modifying recurring events stored on a remote calendar
  • Fixed Today was difficult to pick out visually in the month/multiweek calendar views
  • Fixed Columns in Today Pane were not resizable
  • Fixed Calendar event text could render outside the confines of the event block
  • Fixed Event time and event name were not vertically aligned
  • Fixed Improved formatting of event descriptions with long links, such as Zoom invites
  • Fixed RSVP replies to invitations sometimes sent from the wrong email address
  • Fixed Various UI and theme improvements, especially to dark themes
  • Fixed Various security fixes

Known Issues

  • Unresolved: chat encryption fails on 32-bit Windows builds