Microsoft Teams Voice Deployment: Direct Routing Licensing, PSTN Choices and AI Call Requirements

What the channel is saying​

The report's main message is that no single endpoint wins. Rebecca Penman of Infinitel Communications says businesses now have office-based, hybrid and mobile staff. She argues users should be able to move between desk phones, desktop apps and mobile devices without changing how they communicate.

Jack Michalski of TSI sees movement toward softphones, mobiles and laptops, with headsets mattering more for heavy callers. He still sees a place for dedicated desk phones in receptions, education and hospitality.

Steven Try of Snom says resellers are moving away from selling handsets on their own. Voice is increasingly bundled with a PBX, messaging and other tools. His example is a warehouse. It might need durable cordless handsets that hold their signal, or a PA system for announcements. He also notes that most voice traffic is internal, with staff calling colleagues in other departments or sites.

Alex Finn of Evolve IP warns about choice paralysis, compatibility worries and increasingly mixed estates. His advice is to start with user requirements, then consider certification, interoperability and onboarding.

The Teams angle​

Martin Boiles of Boom calls Microsoft Teams the most effective endpoint many firms already own but underuse. He says it can act as a business phone system with call routing, queues and voicemail.

Ben Merrills of Jola recommends Teams with Direct Routing for most UK businesses. His argument is that the licences are already committed, and that an outside carrier cuts per-user cost compared with Calling Plans. The report gives no pricing or cost model, so this is a provider's view and not a measured result.

Jola also says it delivers the Session Border Controller (SBC) layer as a service. That means the partner does not host or certify one.

What Microsoft's documentation says​

Microsoft's licensing reference is plain that Direct Routing lets you connect a supported, customer-provided SBC to Teams Phone, and requires a Teams Phone licence. Microsoft's planning page lists Microsoft Teams and Teams Phone as the licences Direct Routing users need. It adds that additional licensing may be required depending on your deployment.

So "the licences are already committed" only holds if Teams Phone is already in the estate. Many customers have Teams but not the phone add-on.

Other points from Microsoft's planning guidance:

• Certified SBCs only. Only Microsoft-certified SBCs are supported with Direct Routing. Managed SBC services shift who hosts the box, but the certification requirement stays.
• Endpoints. Direct Routing supports Teams desktop and mobile clients, Teams-certified phones and Common Area Phones. That fits the report's mixed-estate theme.
• Mixing connectivity. Microsoft's planning page says organisations can combine Direct Routing with Calling Plan or Operator Connect in one tenant. A common pattern is Direct Routing for third-party PBXs and analog devices.
• Numbers. Microsoft states that Teams Phone is a separate add-on, and external calling also needs a PSTN connectivity option. The phone-number guidance adds that telephone numbers come from the PSTN provider and are not part of the licence.

Boom's two routes, and why the distinction matters​

Boiles describes two ways to use Teams voice through a provider like Boom. In the first, full Direct Routing into the native Teams dialler needs a Teams Phone licence per user. In the second, the provider's own interface runs as an app inside Teams, and calls run over the provider's platform instead of Microsoft's calling plan. In that case customers do not need to buy Teams Phone licences.

The report presents this as the commercial opportunity. The practical consequence is that users get a different experience in each route. One uses the native Teams dialler and the other uses a third-party app within Teams. Partners should spell that out before signing anything.

Number porting is a real headache​

Merrills names porting as a stumbling block. He lists incomplete letters of authority, number ranges split across providers, addresses that don't match the losing provider's records, and port dates that move at a week's notice. Jola says its SIP Manager handles porting with e-signature and pre-order validation. That is the company's description of its own service, and nothing here independently verifies it.

Microsoft's guidance supports the underlying point. In a Direct Routing setup, you reserve or port numbers through your Direct Routing PSTN partner directly. The numbers can then be uploaded into Teams for management. Microsoft's page says uploading is optional. It also says assigning a number to a user adds it to the inventory automatically.

Microsoft documents one porting step worth knowing. When moving Direct Routing numbers to another PSTN option, you must release them from Microsoft's number inventory before the port. You do this with the New-CsOnlineTelephoneNumberReleaseOrder cmdlet, after unassigning the numbers from users.

Queues, auto attendants and AI voice agents​

Boiles lists queues as a Teams feature. Microsoft's prerequisites for voice applications show there is licensing behind them:

• At least one Teams Phone licence is needed.
• A free Teams Phone Resource Account licence is needed for each resource account.
• Outbound PSTN scenarios add requirements. These include external transfers, callback and on-behalf-of calling.
• For Direct Routing numbers, the resource account needs an online voice routing policy for those outbound scenarios.
• For Microsoft Calling Plan numbers, Microsoft says that from 1 November 2025 a funded pay-as-you-go licence or Communications Credits is required. The documentation says outbound calls fail without one.

Microsoft's same page also covers Teams Phone Agent, which is its own AI voice agent. It lists Copilot credits and spending policies among the requirements.

AI transcription and Copilot: check the prerequisites​

Michalski talks up transcription, summaries and notes. Microsoft's Copilot-in-calls documentation sets out what that needs in Teams:

• For 1:1 Teams calls, users need an add-on Microsoft Copilot licence.
• For PSTN calls, they also need a Teams Phone licence and a calling plan.
• Transcription must be turned on through the Teams calling policy for Copilot to be available after a PSTN or 1:1 VoIP call. Otherwise Copilot works only during the call.
• Copilot is not available in end-to-end encrypted calls.
• If a 1:1 call becomes a group call, the recording and transcript stay with the original 1:1 chat, and added participants can't access them afterwards.

On the compliance side, Microsoft's calling policy page lists a setting that requires participant agreement for recording and transcription. When it is on, participants' audio, video and content sharing stay off until they agree. For anyone selling call recording and sentiment analysis, that is a governance conversation to have with customers early.

About the headset claim​

Jessica Harrison of EPOS says headsets and speakerphones lead the hardware side. She says the Impact 1000 has native Bluetooth and a word accuracy rate of more than 99 out of 100 when working with AI assistants, voice prompts and people. The report gives no test method, conditions or independent validation. Treat it as a manufacturer claim and ask for the methodology before using it in a proposal.

A practical checklist​

This synthesis is based on the report's themes and Microsoft's documentation:

1. Profile users first. Separate desk-based, hybrid, mobile and shared-space users, as Penman and Finn suggest. Reuse handsets that still work, as Penman describes.
2. Check licences. Confirm whether Teams Phone is already present. Don't assume a Direct Routing quote avoids it.
3. Pick the PSTN path per population. Calling Plan, Operator Connect, Direct Routing and Teams Phone Mobile can coexist in one tenant.
4. Plan the SBC. It must be certified, with an FQDN in a verified domain, a public certificate and the right firewall rules. Managed services can carry this.
5. Audit numbers before porting. Check ranges, addresses and authority paperwork.
6. Set calling policies. Decide on recording, transcription and Copilot behaviour before rollout.
7. Test before go-live. Microsoft's checklist includes inbound and outbound PSTN calls, emergency calling, failover and call quality.
8. Train users. Michalski's point stands: software that nobody uses is wasted spend.

The bottom line​

The report is useful as a snapshot of how channel partners sell voice, but it is mostly vendor and reseller perspective. It supplies no market sizing, adoption data, cost comparison or productivity measurements. The strongest takeaway for Microsoft-centric IT teams is practical. Teams can be the voice front end, but cost and capability depend on the PSTN route, Teams Phone licensing, number logistics and AI policy settings. Those are worth pinning down before any endpoint is chosen.