Older Teams phone apps lose calendar access in early October
Reviewed by Helen Jones
Microsoft is cutting calendar access on older Teams apps for iOS and Android. Users need a current build by the end of September 2026. From early October, outdated mobile clients will no longer show the calendar. Desktop and web Teams are not affected. The change lines up with Exchange Online turning off Exchange Web Services in stages from 1 October 2026, with full retirement planned for 1 April 2027. Microsoft says the cutoff keeps mobile calendar reliable as that older connection method goes away. Phones that update automatically usually pick up a safe version. Company-managed devices often wait on IT to push the app. Admins can briefly keep EWS alive for listed apps until the April 2027 shutdown, but that is a stopgap, not a plan.
For many people the phone is the only place they accept invites, check the next meeting, or catch a change while away from the laptop. When that calendar view fails, the day does not pause. Meeting decisions move back into chat pings, inbox scrolling, and mental lists, which is the same scatter already felt across flags, Planner, and notes. What changed is the deadline. This is no longer a vague backend retirement. It is a hard mobile break timed to early October, so a neglected phone app can quietly remove the one Microsoft 365 surface that still felt connected on the go. Web and desktop keep working, which makes the failure easy to miss until you need the calendar between meetings.
Analysis
This is a small trust check, not a reason to redesign your whole system. Open Teams on your phone this week, confirm it can update and that calendar still loads, and if the app is locked by the company, ask whoever manages devices to push a current Teams build before the end of September.
Source note
Pulse published by Collab365 Spaces, reviewed by Helen Jones on . Cite as "Older Teams phone apps lose calendar access in early October", Collab365 Spaces. 3 sources referenced.