With the new Outlook for Mac, we have reimagined the experience that you know and love, bringing even more power and simplicity to the product. Notably, the new design will be available to use via an in-app toggle (found in the top-right corner).
Microsoft detailed the improvements and changes it has made with the upcoming version of Outlook for Mac in a press release and blog post today. The new Outlook for Mac is designed to look and work great with macOS Big Sur, includes speed improvements, new UI, tools, improved customization, and more. Microsoft has been working on a totally redesigned version of Outlook for Mac since last fall and the public release of the big update is slated for mid-October.