Why do personal Microsoft accounts generate a Teams link only when we omit onlineMeetingProvider in request, and is this default behaviour officially supported?

We have a question regarding Teams meeting creation using the Microsoft Graph API (/me/calendar/events) for personal Microsoft accounts (e.g., Outlook.com / Hotmail.com).

When we include "onlineMeetingProvider": "teamsForBusiness" in the request body for a personal Microsoft account, the API creates the event in Outlook Calendar but does not generate a Teams meeting link.

However, when we omit the onlineMeetingProvider field, a Teams meeting link is successfully generated for the same personal account.

We would like clarification on the following:

1. Is omitting onlineMeetingProvider and relying on the default behaviour a supported and stable approach for personal Microsoft accounts?

Why does explicitly setting onlineMeetingProvider: "teamsForBusiness" prevent the meeting link from being generated?

Failure Case

Request

{
  "...": "...",
  "isOnlineMeeting": true,
  "onlineMeetingProvider": "teamsForBusiness"
}

Response

{
  "...": "...",
  "isOnlineMeeting": false,
  "onlineMeetingProvider": null
}

Result: Event is created, but no Teams meeting link is generated.

Success Case

Request

{
  "...": "...",
  "isOnlineMeeting": true
}

Response

{
  "...": "...",
  "isOnlineMeeting": true,
  "onlineMeetingProvider": "teamsForBusiness",
  "onlineMeeting": { "joinUrl": "..." }
}

Result: A Teams meeting link is successfully generated.

• We reviewed the following documentation, which states that Teams meeting creation is not supported for personal Microsoft accounts — but our observed behavior seems to differ:
  • Microsoft Teams limits and specifications
  • Microsoft Q&A thread on personal accounts and Teams Graph API
  Could you please confirm whether this is:
  • expected behaviour, or
  • a potential inconsistency in the Graph API for personal accounts?