Certified contact centre integration models and Teams Phone extensibility

What it does

Microsoft's certification programme for third-party contact centres that work with Teams, sorted into three integration models — Connect, Extend and Unify — by how the vendor's platform touches Teams Phone. Teams Phone extensibility is the newest plumbing under Unify: it lets an Azure Communication Services application answer and place calls on Teams Phone numbers.

Key facts

Connect: the contact centre platform links to Teams Phone through certified SBCs and Direct Routing. Telephony and routing live in the vendor's cloud; Teams is where the agent or expert is reached.
Extend: the vendor runs in Microsoft's cloud using Azure bots and the Microsoft Graph Communications APIs, delivered as a Teams app. Calls stay on Teams Phone and the agent works in Teams.
Unify: built natively on Azure Communication Services (Call Automation and Calling SDKs), with Azure OpenAI and other Microsoft services alongside, running on Teams calling infrastructure.
Several vendors are certified under more than one model (Anywhere365, for example, appears under both Extend and Connect). The current list is in the Microsoft partner solutions directory linked from the Learn page.
Support: Microsoft only supports certified solutions, and the partner is first line. Microsoft can reject cases involving non-certified products.
Teams Phone extensibility (TPE) uses a Teams resource account holding the number and licence, an ACS resource, Call Automation for server-side control/IVR, and the Calling SDK for the agent client.
TPE works with Calling Plans, Direct Routing and Operator Connect numbers. ACS usage is billed pay-as-you-go on the Azure subscription.
TPE agents are "dual persona" — the agent experience is the ACS application, not the Teams client.
TPE supports inbound to a Teams service number, outbound as that number, add/transfer to Teams users and external numbers, consult a Teams SME, play/recognise (DTMF and speech), real-time transcript and audio streaming, UUI/X-header passing and ACS recording.
TPE doesn't honour Teams convenience or compliance recording, forwarding rules, simultaneous ring, shared line, call park or location-based routing, and agents can't turn on Teams captions.
On-behalf-of outbound via Graph or TPE on Calling Plan numbers needs pay-as-you-go or Communications Credits on the resource account since November 2025.

When to use / skip

Pick the model by where the client wants routing, recording and reporting to live, not by vendor brochure. Connect suits clients already committed to a big CCaaS platform (Genesys, NICE, Five9 and the like) who want Teams users reachable for expert consult; it's mature but you're running two telephony estates. Extend suits Teams-centric organisations who want agents in the Teams client with a richer queue engine on top — the classic Anywhere365, Luware or ComputerTalk deployment. Unify and TPE are where Microsoft's own investment is going, and it's the route Dynamics 365 Contact Center uses for voice on Teams Phone numbers; that has its own KB.

Skip the whole question for basic queues. If round robin, a callback and a supervisor view are enough, native queues plus the Queues app will do it. The native-vs-certified choice itself sits in the decision guides.

Configuration decisions

Integration model, which decides who owns the PSTN: the vendor's SBCs (Connect) or Teams Phone numbers (Extend/Unify).
Agent client: Teams client with a vendor app, a vendor desktop, or an ACS-based agent app.
Number strategy: keep DDIs on Teams resource accounts or port them to the CCaaS carrier.
Recording: Teams compliance recording (Extend), the vendor's own recorder (Connect), or ACS recording (TPE) — they aren't interchangeable.
Licensing per agent: Teams Phone is assumed for Extend; TPE adds ACS consumption; Connect adds the vendor's seat licence on top.
Azure tenancy and data residency for Extend/Unify components — many run in the vendor's Azure, some can be customer-hosted.

Gotchas

"Certified" means certified for a model, not for every feature on the vendor's datasheet. Check which model the feature you're buying actually runs under.
Connect deployments often break Teams-native features agents expect — presence sync and transfers back into Teams queues need explicit design.
TPE doesn't honour Teams compliance recording. If the client's FCA recording obligation is met by a Teams policy-based recorder, TPE calls fall outside it.
PSTN callers hear an announcement whenever recording starts or pauses on a TPE call with a Teams or dual-persona user. Learn's FAQ says partners suppress it by request to Microsoft. An October 2026 docs change adds a Teams meeting policy route (DisableAudioAnnouncementsForResourceAccounts set to $true, assigned to the resource account), but it wasn't on the live FAQ at the time of writing. Check which applies before promising a silent recording start.
TPE agents can't park calls or use shared line, and adding a Teams user ignores federation/external access config. Test transfer to Teams users early.
Mixing PSTN connectivity types between a resource account and transfer targets isn't supported. Integrations that look fine on a single trunk break when the client is half-way through a Direct Routing migration.
Unify vendors and TPE sit on Azure Communication Services, which retires as a standalone offering on 30 September 2028. TPE itself is unaffected, and it's now the supported route for Call Automation and PSTN. A vendor still running standalone ACS calling has a migration to do, so ask for their plan. See ACS retirement: what lands on Teams voice.
Extend solutions run bots in someone's Azure subscription — usually the vendor's. Ask where they're hosted and which region, because that's where call media is processed.

Consultant notes

Ask for the vendor's certification model and version in writing, plus their Microsoft support escalation path.
Draw the media path for one inbound call per model before the design workshop — it settles most arguments about latency, recording and who owns the SBC.
For Extend vendors, get the Graph permissions and app consent list early. Security teams want to review bot application permissions.
With TPE or D365 Contact Center, budget ACS consumption separately. It's an Azure bill, not a Microsoft 365 licence line, and finance will ask.
Keep a few native queues for internal lines even when a certified contact centre goes in. Not every helpdesk needs a CCaaS seat.

Worth revisiting as Teams Phone extensibility closes its feature gaps — compliance recording support is the one to watch