It is no secret that Microsoft wants users to like its New Outlook for Windows offering and really wants those who haven"t yet switched over to the new app to do so already. The company has its reasons to feel like that.
Back in December of 2024, Microsoft had shared a timeline for when Microsoft 365 Enterprise users would be switched over to New Outlook for Windows from the classic app. At the time, the company had said that the big switch would happen in April 2026, which means it was set to happen around one month from now.
So if you were preparing to make the jump, you can rest easy, as Microsoft has given more time. The company, last month, shared an update to this timeline and it has said that the opt-out phase for New Outlook for Windows has been pushed back to March of 2027, so admins and users alike will get a whole new year for making the switch.
In the newly updated message on the Microsoft 365 Admin Center portal, the tech giant has written:
"Microsoft is updating the opt‑out phase start date for new Outlook for Windows in Enterprise environments from April 2026 to March 2027. ... We’re seeing strong and accelerating adoption of new Outlook as organizations progress on timelines that match their readiness. At the same time, we continue to invest heavily in expanding capabilities and addressing feedback from customers who want to go further with new Outlook. To ensure organizations have the time they need to prepare—and to fully realize the value of ongoing innovation—we’re extending the opt-out timeline and providing 12 months of lead time as we continue delivering key features and improvements."
If you have access to the Microsoft 365 admin center portal, you can view the message under ID MC949965.
If you are not sure about what the opt-out phase is, this is the stage in the Outlook rollout where the app will be on by default, but users will still have the option to opt out via the toggle.