Microsoft Teams Phone System UK: How It Works & Costs

What Is Microsoft Teams Phone?

Microsoft Teams Phone is a cloud-based business telephone system built into Microsoft Teams. It adds PBX-style call handling—such as transfers, voicemail, auto attendants and call queues—to a Microsoft Teams environment. With suitable licences and a connection to the public telephone network, staff can make and receive calls to ordinary UK business, landline and mobile numbers.

Teams meetings, internal Teams-to-Teams calls and a telephone service for customers are not the same thing. A company can use Teams daily for chat and meetings but still have no configured external telephone calling. In most deployments, enabling Teams Phone is only one component of the complete system.

TEAMS PHONE EXPLAINEDMicrosoft Teams Phone for UK Business Calling

For a UK business, the real purchase decision is therefore not simply “Do we have Teams?” It is whether the organisation can assemble licensing, calling service, numbers, call handling and accountable support into a working, affordable telephone system.

How Does a Microsoft Teams Phone System Work?

Teams Phone provides the call-control layer within Microsoft’s cloud services. Your chosen PSTN connection transports external calls; the Teams tenant applies policies, number assignments and call routing; then the call reaches an employee, queue, auto attendant or authorised shared destination. An office computer, smartphone or supported desk phone can be an endpoint, but the device does not replace the underlying voice-service contract.

UK BUSINESS TELEPHONYHow Teams Phone Fits Into a Business Calling Service

What Happens When a Customer Calls?

1. The public number receives the call. The number may be supplied through Microsoft or a participating communications provider, depending on the design.
2. The PSTN route connects it to Teams. Teams Phone recognises the number assignment or voice application and applies the approved inbound configuration.
3. The relevant destination is selected. A user may ring directly, or an auto attendant may route the call into a team or call queue.
4. The employee answers on a supported device. Their experience depends on sign-in, policies, connectivity and available call-handling features.
5. Fallback rules decide the next step. Busy or unanswered calls need configured overflow, voicemail, an alternative agent or a documented continuity arrangement.

An external call from an employee follows the reverse pattern. Teams Phone applies user permissions and a dialling route, then sends the call through the selected PSTN service. A Teams-to-Teams conversation between colleagues may not need a PSTN route at all.

What Do You Need to Make External Calls?

Before ordering a new supplier package, check which elements are already included in your Microsoft 365 agreement and which are not. The exact entitlement can differ by tenant, subscription family and purchase channel. The following checklist prevents buying a telephone licence without the service needed to use it.

Teams Phone licensing is generally assigned per person using Teams Phone. Service functions such as auto attendants and call queues can also require appropriately licensed resource accounts, which are different from employee accounts. Shared Calling is a separate way to provide calling without issuing every user a dedicated public number; neither approach means no licence is needed.

Four Ways to Connect Microsoft Teams to UK Telephone Numbers

Microsoft documents four principal PSTN connectivity approaches. They have different ownership and operational consequences, and eligible organisations can mix them for different departments or locations. The correct choice depends on number compatibility, supplier relationships, mobile-working needs and who will manage the telephony layer.

This is a selection overview, not an exhaustive Operator Connect versus Direct Routing comparison. The detailed commercial and operational side-by-side belongs in its own approved planned guide rather than being duplicated here.

Which Business Calling Features Are Included?

Teams Phone can provide everyday PBX features including an external dial pad, call hold, consultative transfer, forwarding, voicemail and caller-history functions. Auto attendants and call queues can direct customers to reception or a department. Some advanced intelligence, recording and queue-supervision capabilities depend on separate eligibility or configuration; do not assume that all features appear under the same licence.

Basic Call Queues Are Not the Same as Advanced Queue Supervision

Microsoft’s core auto-attendant and call-queue functions are designed to route calls. The separate Queues app provides more advanced agent and supervisor workflows such as enhanced queue views and reporting; Microsoft’s guidance identifies additional Teams Premium and Teams Phone requirements for relevant users. Confirm the exact capability and entitlement before presenting Teams as a complete contact-centre replacement.

The right buyer question is not just “Does Teams have call queues?” but whether the available call flow, reporting, transfer behaviour and licensing match the workload your reception or customer-service staff actually handle.

Microsoft Teams Phone Licensing and UK Costs

Licensing is the most common area for incomplete quotes. Some Microsoft 365 subscriptions include relevant Phone entitlements; others require Teams Phone Standard as an additional subscription. A separate Teams entitlement may also be required. If external numbers are needed, the PSTN arrangement must be included or sourced independently.

The prices below are Microsoft’s published UK online examples checked in October 2026. They are monthly equivalents of annual-payment subscriptions, exclude VAT, and may vary by eligibility, channel or subsequent pricing changes. Verify the offer at purchase time.

Source: Microsoft’s UK Teams Phone pricing page. These are not complete managed-system quotes and do not include every possible Teams licence, VAT, device, migration or support charge.

Worked UK Buying Example: Twelve Office Users

Suppose a small company has 12 licensed users who need public outbound calls. At the advertised £13.10 domestic-calling bundle, the illustrative licence subtotal is £157.20 a month excluding VAT (12 × £13.10), assuming every user is eligible for that exact offer. This is a calculation example—not a provider quotation or evidence of the business’s total telephony cost.

Still check the underlying Teams entitlement, actual call usage, reception and service-number requirements, audio-conferencing extras where relevant, devices, number porting, setup, ongoing support, networking and continuity. If an Operator Connect supplier provides the calls instead, obtain a separate carrier quote and verify how your Teams Phone entitlement is licensed.

Build a Like-for-Like Whole-System Quote

Ask suppliers to show a per-user and per-business subtotal with VAT status clear. Microsoft may bill one component while a telephone partner bills others. The buyer needs one comparison that covers all required layers.

Can You Keep Your Existing UK Business Phone Numbers?

Often it is possible to retain a business’s established geographic and non-geographic numbers, but it is not automatic. The receiving service, number type, losing carrier, current contract and porting process all matter. A successful Teams demo on a temporary number does not demonstrate that your 020, 0116, 03 or service number can move to the intended provider.

Microsoft publishes a dedicated UK phone-number management reference for acquiring and porting numbers into Microsoft’s own service. It gives an indicative 12–30 business-day porting period and requires a letter of authorisation. Its published restrictions include limitations around partial porting and number categories. Those are Microsoft Calling Plan rules; Operator Connect and Direct Routing carriers may have their own procedures and eligibility.

Four Questions Before Requesting a Port

1. Who currently controls the numbers? Obtain the account name, service agreement, published DDIs, main number and any service numbers.
2. Which receiving route will hold them? Name Microsoft, the Operator Connect provider or the Direct Routing carrier, rather than saying only “move to Teams”.
3. Which numbers must stay grouped? Check business-hours menus, queue numbers, geographic identities, 0800 services and emergency or fax dependencies individually.
4. What happens on cutover day? Agree port timing, emergency/location information, external inbound/outbound calls, caller ID, voicemail, rollback and responsibility for failed ports.

The site’s UK business number-porting guide covers the wider transfer process. This section establishes the Teams-specific questions, rather than replicating a full number-porting manual.

Can Staff Use Desk Phones, Mobiles and Shared Numbers?

Microsoft Teams Phone can be used on a Windows or Mac computer with a suitable headset, on the Teams mobile app and on supported Teams-certified phones. Availability and behaviour are not identical for every endpoint, so check actual product certification and any shared-area licensing before committing to equipment.

Shared Calling: Public Calling Without a DDI for Every Employee

Microsoft’s Shared Calling guidance describes a design where appropriately licensed Teams Phone users make external calls using a shared resource-account number rather than each receiving their own individual external number. The resource account is associated with an auto attendant, and policies and emergency-calling configuration still need to be established.

This can be useful for back-office users who need occasional external calling but do not require a personal DDI. It is not a way to avoid licensing every Teams Phone user. Confirm inbound reception expectations, outbound caller identity, emergencies, minute/credit arrangements and whether Shared Calling is available with the chosen carrier design.

Emergency Calling, Security and Reliability

A cloud telephone solution still relies on several systems beyond the Microsoft platform. A working Teams app does not by itself prove the carrier, local internet connection, business number, emergency-location information or office power protection will behave correctly in a failure.

999/112 and Caller-Location Checks

Emergency access and caller-location obligations must be designed with the selected regulated communications provider. Check how the chosen PSTN service handles 999 and 112, what address or dynamic location information it uses, and how staff working remotely are covered. This deserves particular attention for multi-site businesses, shared offices and employees who use the same laptop at home and at work.

Ofcom also addresses access to emergency organisations during power cuts. Agree the practical alternative for vulnerable users and any business-critical location. Do not make test calls to real emergency numbers without an approved procedure with the service provider.

Reliability Has More Than One Failure Domain

Microsoft’s Call Quality Dashboard can help administrators analyse call quality, but it does not supply a substitute broadband connection or guarantee third-party carrier recovery. Use the site’s separate VoIP Call Quality and Reliability guide for broader networking and fault-isolation methods.

Privacy, Recording and Administration

Assign appropriate administrative roles, apply multi-factor authentication and least privilege, establish retention and recording policies, and determine who can access call records. If calls are recorded or monitored, check the applicable UK GDPR and ICO obligations, explain relevant monitoring appropriately and distinguish policy-based recording products from ordinary voicemail or transcription features. Advanced AI/call-summary features should only be promised after checking their actual licence, availability and data-governance configuration.

Is Microsoft Teams Phone Right for Your Business?

Teams Phone is often a credible option where a company already uses Microsoft Teams heavily and wants business calling inside the same employee experience. It is not automatically the cheapest or simplest answer for every organisation—especially where large inbound queues, unusual telephony devices, specialist integrations or limited internal Microsoft administration capacity are involved.

Teams Phone should be evaluated as an operating model: its suitability depends on the exact tenant, number plan, support partner, user roles and the business’s tolerance for administration complexity.

How Do You Move From an Existing PBX to Teams Phone?

A safe migration needs a documented telephone estate before any number porting. Inventory live numbers, queues, reception menus, alarm/lift/fax or payment-terminal dependencies, staff extensions, current support contacts and out-of-hours routes. A meeting rollout checklist is not sufficient for business-critical telephony.

Six Stages for a Controlled UK Rollout

1. Discover the current estate. Map numbers, carriers, devices, sites, reception paths, special lines and which people own contracts and administration.
2. Confirm licences and PSTN model. Validate actual tenant SKUs, calling method, ports and geographic/mobile/service-number eligibility before ordering.
3. Design call flows and continuity. Configure main number handling, open/closed hours, queues, transfers, emergency-location rules and agreed backups.
4. Pilot on controlled numbers. Test a representative mix of staff, headsets, certified devices, home workers, departments and external carriers.
5. Port and cut over in stages. Agree change windows, numbers included, operational ownership, communication to users and a formally approved fallback for incidents.
6. Verify after go-live. Test every public number externally, inspect transfer and voicemail behaviour, review call quality and reconcile carrier/Teams invoices.

Ask the provider to demonstrate the correct route for both incoming and outgoing public calls. Include at least one actual mobile-network call from outside your business, rather than relying only on internal Teams test calls. Where an existing number cannot be ported to the selected operator, establish the alternative before advertising a go-live date.

For the general infrastructure, router and device preparation steps, see the existing business VoIP setup guide.

Microsoft Teams Phone Readiness Checklist

Use these twelve questions in the supplier meeting. Each should receive an explicit answer, accountable owner and practical demonstration before the service is accepted. The boxes below are a private on-page checklist; they do not save information or send it to any provider.

Frequently Asked Questions

Sources and Technical Documentation

This guide uses Microsoft product documentation and relevant UK regulatory guidance. Availability, pricing, licence entitlements, supported numbers and provider arrangements can change: verify the exact customer agreement and current official documentation before ordering.

• Microsoft: Teams Phone Product and UK Pricing — Official scope and currently advertised UK bundle conditions.
• Microsoft Learn: Set Up Teams Phone — High-level licensing, voice enabling, numbers, emergency calls, attendants and queues.
• Microsoft Learn: PSTN Connectivity Options — Four PSTN routes, operator responsibility and supported number types.
• Microsoft Learn: Teams Phone Add-on Licensing — Teams Phone entitlement and Shared Calling relationships.
• Microsoft Learn: UK Number Management — UK Calling Plan acquisition and porting conditions.
• Microsoft Learn: Plan Teams Phone Mobile — Participating mobile operators and service-number limitation.
• Microsoft Learn: Shared Calling — Shared user/public-number operation, policy and emergency-location requirements.
• Microsoft Learn: Resource Account Licences — Licensing for auto attendants and call queues.
• Microsoft Learn: Teams Premium Licensing — Advanced Queues app requirements and feature scoping.
• Microsoft Learn: Call Quality Dashboard — Call quality investigation and analytics.
• Ofcom: Emergency Access in a Power Cut — UK voice-service emergency access and power resilience guidance.