Teams contact center integration models

Verified 2026-09-14 · 60 claims · sources tier 2–6

Microsoft Learn defines three integration models for contact center solution providers: Unify, Extend, and Connect 26. Contact center integration with Teams Phone is supported for organizations seeking business tools and workflows beyond native Teams auto attendants and call queues 23.

The Contact center for Microsoft Teams certification program verifies that participating provider solutions meet the quality, compatibility, and reliability expected of Microsoft solutions 4. Microsoft states that the published feature highlights for Extend and Connect do not form an exhaustive list of capabilities for those integration models 18.

Unify model (Teams Phone extensibility)

The Unify integration model enables solution providers to develop native Azure Communication Services-based CCaaS applications using Teams calling infrastructure 54. Microsoft's third-party voice agents planning documentation explicitly equates the Teams Phone Unify integration model with Teams Phone extensibility and links it directly to Azure Communication Services documentation 57. The model extends Teams Phone into CCaaS using Azure Communication Services call automation, the Azure Communication Services calling SDK, OpenAI, and other Microsoft tools 58.

Licensing and provisioning prerequisites

Teams Phone extensibility requires enterprise voice enabled and a Teams Phone license assigned to each agent 28. The associated Teams resource account requires a Microsoft Teams Phone Resource Account license, which Microsoft states is included with the Teams Phone license 47.

Provisioning requires the following administrative actions:

• A Teams administrator must assign the CCaaS provider's Azure Communication Services resource ID to the Teams resource account 45.
• In the quickstart, the resource account must be provisioned using Teams PowerShell cmdlets (New-CsOnlineApplicationInstance, Set-CsOnlineApplicationInstance with -AcsResourceId, and Sync-CsOnlineApplicationInstance), with the Teams Admin Center identified as out of scope for this procedure 41.
• The ApplicationId used during resource account creation must match the CCaaS provider's third-party bot ID; first-party Teams application IDs are unsupported 53.
• After resource account setup, the CCaaS administrator must complete a one-time server consent process to authorize the CCaaS service to receive Teams calls 51.
• To comply with data boundary regulations, the quickstart specifies that the Azure Communication Services resource's data location should align with the Teams tenant location 31.
• The Microsoft Graph API used by developers to list resource accounts (admin/teams/resourceAccounts) appears on the beta endpoint in the quickstart, which Microsoft states is unsupported for production use 46.

Call routing, multi-persona, and controls

Teams Phone extensibility supports Teams Calling Plans, Operator Connect, and Direct Routing for PSTN connectivity 44. For the Teams Phone integration component of Teams Phone extensibility, the current release exclusively supports Teams Phone service numbers 52.

Inbound PSTN calls to the resource account phone number trigger an Incoming Call Event Grid notification to the associated Azure Communication Services resource, which the CCaaS server application answers via the Call Automation SDK 34. Third-party IVR bots can receive calls routed from Teams Auto Attendants and Teams Call Queues (including queue overflow, timeout, and no-agent-available states) as first-class entry points 27. Microsoft lists 3 entry points for third-party voice agent integrations: direct routing to the voice agent, Teams Phone Agent or auto attendant routing, and call queue exception-handling routing 1.

Outbound and mid-call controls operate under specific constraints:

• An agent using a CCaaS client can initiate outbound PSTN calls on behalf of a Teams resource account using the Calling SDK onBehalfOfOptions parameter, presenting the resource account caller ID to external parties 37.
• Personal phone numbers assigned to Teams users cannot be used for outbound CCaaS PSTN calling and are restricted to emergency calling 40.
• Overriding caller identification via SourceCallerIdNumber or SourceDisplayName on a CallInvite is unsupported and generates error 400 code 8523 29.
• Microsoft does not recommend the Call Automation Redirect option for CCaaS scenarios, strongly recommends AddParticipant for adding CCaaS agents, and states that Redirect is not supported for on-behalf-of use cases 49.
• In multi-persona configurations, Teams policy determines whether the Calling SDK client or Teams client rings for inbound calls; no API exists to configure this behavior 50.
• Multi-persona call history is isolated by client: CCaaS calls do not display in Teams, and Teams calls do not display in the CCaaS client 33.
• To synchronize agent presence between personas, ISVs use standard Microsoft Graph presence APIs, which Microsoft notes ISVs already execute in Connect and Extend models 42.
• For emergency calls originating from a custom CCaaS client, PSAP callbacks ring both the CCaaS and Teams clients; calls placed from the Teams client receive callbacks on the Teams client only 43.

PSTN connectivity and carrier billing rules

Since 1 November 2025, standard Calling Plan licenses assigned to Teams resource accounts cannot be used for on-behalf-of or server-initiated outbound PSTN calls in Teams Phone extensibility; resource accounts require a Pay-As-You-Go Calling Plan license backed by Communications Credits or telco overage 39. Microsoft states that Direct Routing numbers are not affected by the 1 November 2025 Teams Phone extensibility outbound licensing change 32. Microsoft says that from 1 November 2025 Teams Phone extensibility on-behalf-of and server-initiated outbound calls over Operator Connect may change depending on the carrier, and may fail without carrier adjustments 38.

For proactive outbound participant moves, latency optimization applies automatically on Calling Plan, requires carrier configuration on Operator Connect, and was not applied to Direct Routing at publication 36.

CCaaS vendors incur Azure Communication Services charges for Calling SDK and VoIP consumption for each call leg established between the CCaaS agent and the call automation bot 35. Base Teams user licenses do not cover consumption generated inside third-party apps or extensions, routing billable consumption to Graph API or Azure Communication Services resources 22. Call recording in the initial release centers on Azure Communication Services Call Recording for inbound and outbound CCaaS paths 48.

As of the August 2026 documentation update, AudioCodes (VoCA Conversational Interaction Center) is the only certified provider listed for the Teams Unify Integration Model for voice agents 59.

Extend model

The Extend integration model integrates directly into the Teams client platform using Microsoft Graph Cloud Communications APIs and Teams Graph APIs 13. In this architecture, all contact center call processing and call control operations rely on the Teams Phone system 16.

Feature highlights specify Teams as the primary calling endpoint, centralizing call controls within the Teams client UI 15. In this deployment model, the CCaaS solution provider functions as a telephony carrier alongside Microsoft 365 14.

Media and recording constraints

Microsoft's licensing terms explicitly prohibit using Microsoft Graph Cloud Communications APIs to record, persist, or extract derived data from call media 17. WarmTransfer's reading of the sources is that Extend-model implementations cannot rely on Graph Cloud Communications APIs for contact center media recording and must rely on an alternative mechanism 19.

Where solutions implement application-hosted media bots, Microsoft requires that production bots be written in C# or .NET and hosted on a Windows Server guest operating system inside Azure, explicitly excluding deployment via Azure web apps 3. Microsoft notes that the underlying Real-time Media Platform for bots remains in developer preview and is subject to change 2.

Connect model

The Connect integration model links CCaaS platforms to Teams Phone infrastructure via Microsoft-certified session border controllers (SBCs) and Direct Routing 9.

Key capabilities and licensing requirements include:

• Support for multitenant SIP trunking, permitting a single provider-hosted SBC to serve multiple customer tenants 7.
• Office 365 authentication enabling agents to authenticate against their Microsoft tenant from the CCaaS application 8.
• Teams agent availability reporting and support for transfers and group calls with Teams users 6​10.
• Agents operating within the external CCaaS platform do not require a Teams Phone System license; conversely, any Teams user targeted for call transfers must have an active Phone System license and assigned phone number 5.

Microsoft limits Direct Routing support solely to certified SBC appliances, reserving the right to decline support incidents involving uncertified hardware 11. Microsoft is currently not accepting new vendor nominations for Direct Routing SBC certification 12.

Support boundaries

Microsoft requires third-party voice agent solutions to originate from certified partners; end users must initiate support requests with the solution provider first, and Microsoft may reject support cases involving uncertified voice agents 60. WarmTransfer's reading of the sources is that deploying uncertified SBC hardware in the Connect model or uncertified third-party voice agents in the Unify model risks placing affected user cohorts outside Microsoft's technical support boundary 20.

See also

See also Microsoft Teams Phone architecture and licensing. See also Teams Phone Direct Routing and SBC certification. See also Teams Operator Connect and Azure Communication routing. See also Teams voice routing policies and dial plans.

Applicability

Across the claims in this article, the evidence covers Microsoft Teams Phone, Microsoft Azure Communication Services, Microsoft Graph, and Microsoft Teams platform across multi-tenant deployments, verified as of 2026-09-14. Specific policy and licensing changes for Teams Phone extensibility outbound calling took effect on 1 November 2025 39. The certified voice agent listing for the Unify model reflects status as of the August 2026 update 59. The Graph API endpoint admin/teams/resourceAccounts applies to Graph beta 46.

What remains uncertain

The following operational aspects are not covered by any claim in this article:

• A capabilities matrix for Calling and Call Automation SDKs under Teams Phone extensibility is not covered by any claim in this article.
• Teams compliance recording certification and its interaction with Extend and Unify models is not covered by any claim in this article.
• Explicit general availability (GA) or preview designations and service level agreements (SLAs) for Teams Phone extensibility are not covered by any claim in this article.
• Current Azure Communication Services billing rates for Teams Phone extensibility call legs, recording, and transcription are not covered by any claim in this article.
• The availability of Teams Phone extensibility and contact center certification across government clouds (GCC, GCC High, and DoD) is not covered by any claim in this article.
• The use of Teams Phone extensibility by Dynamics 365 Contact Center is not covered by any claim in this article.
• Reconciliation of quickstart documentation with outbound licensing connectivity-cost rules is not covered by any claim in this article.
• The Teams Queues app and Teams Premium features as native CCaaS alternatives are not covered by any claim in this article.

6 claims on this topic await human review and are not used in this article.

WarmTransfer. (2026, September 14). Teams contact center integration models. WarmTransfer. https://warmtransfer.net/knowledge/teams-contact-center-integration

@misc{warmtransfer-teams-contact-center-integration,
  title  = {Teams contact center integration models},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/teams-contact-center-integration},
  note   = {Verified 2026-09-14}
}