is it possible to make 1 : 1 call from the microsoft graph api without using bot ?

Hii @Vergil-V

Thank you for the clarification and guidance regarding using Azure Communication Services Calling SDK for reaching users on Microsoft Teams without a bot.

I have a follow-up question regarding licensing on the Teams user side.

During my research and testing, I observed that when attempting to call a Teams user from ACS using their Entra Object ID, the call disconnects unless the Teams user appears to have Phone System (Enterprise Voice) capability enabled.

Could you please confirm:

Does a Teams user require any specific license (such as Teams Phone / Phone System / E5) in order to receive a call initiated from the Azure Communication Services Calling SDK?

Or should this scenario work with standard licenses such as Microsoft 365 Business Basic / Standard / E3 as well?

Thank you for your help.

Hi @Siddhartha Sharma 
Thank you for your follow‑up. 

Based on the additional research, using Azure Communication Services with Microsoft Teams users requires a Microsoft Entra tenant that includes users with a valid Teams license. This includes licenses such as Microsoft 365 E5, A3, Business Standard, Business Basic, and other eligible plans listed in the Teams license requirements to use Azure Communication Services support for Teams users | Microsoft … 

Further, a Teams Phone license is also required, and Enterprise Voice must be enabled, as outlined in Enable interoperability with Teams - An Azure Communication Services concept document | Microsoft L… 

I hope this provides additional insight and helps clarify the requirements. 

Hi @Vergil-V ,

Thank you for the clarification on the licensing requirements.

Let me explain my complete requirement with an example to see if Azure Communication Services can support this scenario:

My Use Case:

I have an organization with two types of users:

1. Employees - Internal staff who will use our custom portal
2. Customers - External users with regular Microsoft Teams accounts (But we'll add the customer in the same tenant)

Required Functionality:

• Employees should be able to log into our portal and initiate calls directly to customers' Teams accounts
• Customers would only have standard Teams accounts (no special subscriptions or licenses)
• I need to maintain call history for each employee for compliance and tracking purposes

Essentially, I'm looking to build a solution where our employees can reach external Teams users through our portal, without requiring those external users to have enterprise licenses.

Is this achievable with Azure Communication Services, or would you recommend an alternative approach?

Thank you for your continued support.

Hi @Siddhartha Sharma

Regarding the scenario involving Teams for Home users, which are Teams users without a business license tier, Azure Communication Services does not support interoperability for this case. 

For reference, please see: Capabilities for Teams external users - An Azure Communication Services concept document | Microsof… 

In addition, when using your own customer portal, Azure Communication Services currently supports scenarios where the portal joins a Teams meeting that is initiated by a Teams user. At this time, a Teams user is not able to directly join a one-to-one call that is initiated from the ACS Calling SDK or from a custom customer portal. 

For reference, please see: Teams interoperability - An Azure Communication Services concept document | Microsoft Learn 

That said, based on my understanding of your current situation, Azure Communication Services does not appear to support the scenarios you described. 

If you would like additional perspectives or alternative approaches, you may find it helpful to engage with the broader technical community through https://techcommunity.microsoft.com/ and https://github.com/orgs/community/discussions. These forums often include discussions from engineers and partners who have worked through similar use cases and can share practical insights. 

I hope the information shared helps provide more clarity and supports your next steps.