Today, we are announcing the Public Preview of the Exchange Online Admin API – a REST based, cmdlet style administrative surface specifically designed to help organizations migrate away from EWS for specific Exchange admin scenarios and modernize automation workflows over HTTP.
Context
Exchange Web Services (EWS) is scheduled for deprecation in October 2026, yet many organizations still depend on EWS for specific Exchange administrative tasks due to unavailability of the alternate API for these scenarios. The Admin API provides a REST based, cmdlet style alternative for these scenarios, enabling modern automation while preserving familiar semantics for Exchange administrators.
Note: The Admin API is not a full REST replacement for Exchange Online management. It is designed only to cover the subset of Exchange Online Administrative capabilities that provide alternative for administrative scenarios currently available through EWS. For complete Exchange management, we recommend using Exchange Online PowerShell.
Capabilities available in Public Preview
The Admin API Public Preview includes 6 endpoints. The list of endpoints and supported functionalities are as follows:
- OrganizationConfig — Read tenant wide MailTips related configuration.
- AcceptedDomain — List accepted domains and core domain settings for the tenant.
- Mailbox — Read mailbox properties and manage Send on behalf delegates (view/update).
- MailboxFolderPermission — List, grant, modify, and remove folder level permissions (Inbox, Calendar, subfolders).
- DistributionGroupMember — Retrieve membership for distribution groups.
- DynamicDistributionGroupMember — Retrieve membership for dynamic distribution groups.
For detailed documentation, including request patterns, and endpoint details, visit:
For the most up to date guidance on EWS migration see https://aka.ms/ews1Page.
Availability and roadmap
- Public Preview (Worldwide): Available starting November 17, 2025. Use this phase to evaluate functionality, plan migrations, and share feedback on any gaps between EWS admin scenarios and the Admin API.
- General Availability (Worldwide): Yet to be announced
- Sovereign environments (GCC, GCC High, DoD): Yet to be announced
Currently, API responses include extra properties, but only those listed in each endpoint's documentation will be available at GA. Please refer the individual endpoint documentation for the list of properties that will be available in GA. Any updates to the list of output properties will be announced during the GA release.
Share feedback
Your input during Public Preview is essential. Please use our feedback form to report issues, gaps, or suggestions. Your feedback will help us refine the API and documentation ahead of GA.
Exchange Online Administration and EWS Deprecation teams
