The best Group Chat alternative to Thunderbird is Mailspring, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to Thunderbird and four of them are Group Chat Apps so hopefully you can find a suitable replacement. Other interesting Group Chat App alternatives to Thunderbird are Spike, Missive and Unibox.
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.
Transform your email inbox into a collaborative workspace with Spike. Enjoy integrated chat-like emails, tasks, collaborative notes, and group projects. Seamlessly manage multiple accounts, organize priorities, and schedule meetings across devices.
Collaborative email and threaded group chat for productive teams. A single app for all your internal and external communication.
Unibox is a people centric email client that organizes your messages by person. It avoids having email like a to-do list.
United States
Israel
Canada
Germany
EU
Great alternative, especially for casual users. Simple, streamlined UI, feels fresh.