What’s New in Microsoft 365 - December 2025

As the year winds down, Microsoft continues to roll out updates to improve productivity, collaboration and AI-powered assistance across Microsoft 365 apps. Below are the new updates and features rolling out in December 2025, and a preview of what’s coming in 2026.

OneNote: Update to Copilot Chat Pane

Copilot in OneNote has an updated chat pane experience. When users choose Copilot actions like Summarize Page, Create a Task List, Rewrite Page or Take Notes with Copilot, the results will open in the Copilot chat pane instead of a separate window or appearing directly on the page. 

This makes Copilot more consistent with other Microsoft 365 apps and keeps prompts and results in one place. Users may notice a small workflow change since they will review results in the side pane first then decide what to add to their notes. 

Microsoft Teams: Update to Email Notifications    

Microsoft Teams has updated the sender information for email notifications tied to team and channel join/accept actions. Membership add notifications now come from the team owner’s address, while private join requests and shared channel membership notifications come from no-reply@teams.mail.microsoft

Microsoft Outlook: Automatic Replies Collapsed in iOS/Android

Automatic replies in Outlook for iOS and Android will now be collapsed by default within email threads. Out of office messages and similar auto replies will appear tucked away, with an option to tap and expand them if needed.

This keeps long threads cleaner and makes it easier to focus on the main conversation. Automatic replies are still delivered as usual, they are just shown in a more compact way.

Microsoft Copilot: New Way to Access on Windows Devices

Microsoft is adding a new Microsoft 365 Copilot app to Windows devices that already have Microsoft 365 installed. It will install in the background and appear in the Start menu as a new way to access Copilot features across Microsoft 365.

You may notice the Microsoft 365 Copilot app on your device even if you didn’t install it yourself. The app won’t change your existing Office apps or files, and paid Copilot features will still require the appropriate license.

Coming Soon to Microsoft 365  

Microsoft Whiteboard: Insert Document Feature to Retire January 2026

Starting in January 2026, Microsoft Whiteboard will retire the Insert Document feature, which means users will no longer be able to add PDFs or PowerPoint files directly from OneDrive or SharePoint. Documents already placed on your boards will remain and you can still insert PDFs saved on your computer using the Windows Whiteboard app. For now, the easiest alternatives are uploading images instead or sharing files through OneDrive or Microsoft Teams.

Microsoft Word: Send to Kindle Retiring in March 2026 

Microsoft is retiring the Send to Kindle option in Word. Starting in February 2026 and finishing in early March 2026, users will no longer see Send to Kindle in Word for Windows, Mac or the web.  

Users who rely on this feature can still send Word files to Kindle using Amazon’s Send to Kindle website. Documents already sent to Kindle are not affected.

        Microsoft Publisher: Retiring in October 2026 

Microsoft has announced that Publisher will no longer be supported after October 2026 and it will be removed from Microsoft 365. After that point, Microsoft 365 users will not be able to open or edit Publisher files in the Publisher app.  

If your team still relies on Publisher for flyers, newsletters, or other layouts, now is a good time to plan a transition. Microsoft recommends moving content to other tools such as Word, PowerPoint, or Designer and saving important Publisher files to PDF or another supported format before the retirement date. 

Categories: Science and Technology