Microsoft has begun rolling out a Classic Outlook theme for users of its New Outlook on the web and for Windows, as part of a targeted release that will complete by the end of September. This move is aimed at providing a more familiar experience for those transitioning from classic Outlook to the new version, which still lacks some features found in the older app.
The Classic Outlook theme will become generally available worldwide between late September and late October, but it won’t override existing administrator configurations or automatically migrate users from classic Outlook to the new version. Instead, users will be able to toggle the feature on or off themselves through Settings > General > Appearance. This allows users who prefer the classic look to stick with it while still benefiting from the features of the New Outlook.
The rollout is a response to Microsoft’s growing adoption numbers for the New Outlook client. Despite some enterprise admins expressing concerns about migrating their organizations, Microsoft has seen strong and accelerating adoption rates since its introduction in 2022. The Classic Outlook theme is designed to be an intermediate step for those still getting used to the new layout and design.
Microsoft made this decision after announcing that it would postpone the opt-out phase for businesses from April 2026 to March 2027, giving enterprise admins more time to prepare a staged migration to the new client. This change was made in response to concerns about the transition process, as some users may find the New Outlook interface unfamiliar and difficult to navigate.
The Classic Outlook theme will apply coordinated changes across the Outlook experience, including visual styling, layout, typography, icons, and selected interactions. Once rolled out, users can choose between the classic look or the standard New Outlook design based on their preferences. This move should help ease the transition for those who are struggling with the new interface while allowing them to benefit from its updated features.
In practical terms, this means that users who may have been hesitant to switch to the New Outlook will now be able to use a familiar version of Outlook without having to revert back to the old app. It also provides a clear indication that Microsoft is committed to supporting both versions until it’s ready for organizations to make a complete transition.
Source: Bleeping Computer — 2026-08-21