Exchange Online
Exchange Online EWS fully disabled
April 2027 · April 2027
Microsoft · high confidence · Last verified October 15, 2026
What breaks
Microsoft Learn says EWS is fully disabled in April 2027. Applications that still depend on Exchange Web Services in Exchange Online lose that API, including ones that were kept alive on an allow list until then.
Who is affected
- Any remaining EWS app in Exchange Online, first-party or third-party
- Tenants that kept EWS enabled with an EWSAllowedAppIDs list through the October 2026 phase
- Migrations still waiting on Graph parity for mailbox import/export, public folders, or group mailboxes
Source notes
The Learn timeline says EWS starts to be disabled globally in October 2026 and is fully disabled in April 2027. The October allow-list change is a separate card.
MC1447678 (updated August 24, 2026) named April 1, 2027 as the start of full retirement. Because the current Learn page does not repeat that day, the board date stays at month precision.
Learn’s parity roadmap still lists several Graph gaps with targets in Q3 or Q4 of calendar 2026, and it says estimated dates might change. Generic public-folder CRUD, generic group-mailbox CRUD, and discovery-mailbox access are listed as capabilities that will not be added to Graph.
Learn states the month: April 2027. MC1447678 said full retirement begins April 1, 2027. MC1485116 says tenants that already have an allow list will not have EWSEnabled changed by Microsoft before April 2027, and describes the wider rollout as expected to complete by early July 2027. This card uses April 2027 and does not treat April 1 as a confirmed day.
Sources
Microsoft Learn: Deprecation of EWS in Exchange Online