Your office phone system is only useful when someone can answer a customer call from their desk, home, mobile or a different site without confusion. That is the practical test behind this Teams Phone system review. Microsoft Teams Phone can replace or modernise a traditional business telephone system, but its suitability depends on how your people work, the complexity of your call handling and the support available when something needs attention.
For many UK small and mid-sized businesses, it is an attractive option because Teams may already be central to daily communication. Calls, meetings, chat, voicemail and presence sit in one familiar application. That can reduce the number of systems staff need to learn and help make hybrid working easier to manage.
It is not automatically the right answer for every organisation, however. A business with a busy reception desk, high call volumes or specialist contact-centre requirements needs to look beyond the headline features. The strongest decision comes from reviewing the phone service alongside connectivity, devices, security and support.
What is Teams Phone?
Teams Phone is Microsoft’s cloud-based telephony capability for Microsoft Teams. It allows users to make and receive external calls using business telephone numbers, rather than relying solely on Teams-to-Teams calling.
Each user can have a direct dial number, voicemail and calling features such as call forwarding, simultaneous ring, delegation and call transfers. Administrators can create call queues and auto attendants, so callers can be greeted, routed to the right department and managed outside normal opening hours.
To connect Teams Phone to the public telephone network, a business needs a calling option. In the UK, this is usually provided through Microsoft Calling Plans, Operator Connect or Direct Routing. The right route affects cost, flexibility, number management and the level of technical administration required.
Calling Plans, Operator Connect and Direct Routing
Microsoft Calling Plans offer a relatively straightforward route, with calling bundled through Microsoft. They can suit organisations with simple requirements, though businesses should check call allowances, geographic availability and costs carefully.
Operator Connect allows an approved telecoms provider to supply connectivity directly into Teams. It can offer a simpler management experience than a fully bespoke setup while giving more choice over the carrier and commercial arrangement.
Direct Routing connects Teams to a chosen SIP trunk provider through a session border controller. It is often the most flexible option for businesses that need to retain existing numbers, manage multiple sites, use specialist call routing or integrate with other telephony services. It also needs sound design, active monitoring and accountable support.
Teams Phone system review: where it performs well
The main appeal is consolidation. If staff already use Teams for internal communication and meetings, external calling feels like an extension of the same working environment. Presence information is particularly useful: colleagues can see whether someone is available, on a call or away before transferring a customer.
This helps businesses that have moved to hybrid working. A user can take their business number on a laptop, mobile app, desk phone or Teams-enabled meeting room. The customer calls one consistent number, while the employee has more freedom to work from the location that makes sense that day.
Teams Phone also has a strong administrative foundation. It supports number assignment, policies, call queues, auto attendants, reporting and user management through the Microsoft ecosystem. For an organisation already using Microsoft 365, this can simplify onboarding and offboarding. When a member of staff joins or leaves, IT can manage access, calling permissions and devices within a familiar environment.
Security is another consideration. Teams benefits from Microsoft’s identity and security controls, including multi-factor authentication and conditional access where these are configured. Telephony still needs its own controls – particularly around international calling, number porting, fraud prevention and administration rights – but centralising identity management is a genuine advantage.
For a typical professional services firm, engineering business or multi-site office, these strengths can translate into fewer missed calls and less friction between office-based and remote staff. A receptionist can transfer calls to a colleague working from home without exposing a personal mobile number. A manager can answer urgent calls while visiting a customer. Teams call records can also make it easier to understand whether customer enquiries are being handled promptly.
The limitations to consider before moving
Teams Phone is a capable business phone platform, but it is not a specialist contact centre by default. Basic queues and auto attendants work well for many organisations. If you need sophisticated skills-based routing, detailed agent performance management, outbound dialling campaigns, quality scoring or complex customer relationship management integration, you may need an additional contact-centre solution.
Reception and switchboard requirements deserve particular attention. A busy front desk may require a purpose-built attendant console rather than relying on the standard Teams interface alone. It is worth mapping the current call journey: who answers first, what happens when they are busy, how calls are transferred, and what callers hear outside office hours. Small gaps in this design are quickly noticed by customers.
The quality of a cloud phone service also depends on the network. Teams calls share your internet connection with video meetings, cloud applications and general browsing. Poor Wi-Fi coverage, undersized broadband or weak quality-of-service configuration can affect call quality. A proper assessment should include internet resilience, local network capacity and how calls will continue if a site loses connectivity.
There is also a training consideration. Teams is familiar to many employees, but phone handling is not identical to chat or meetings. Staff need to know how to transfer calls correctly, use shared queues, change call settings and respond to voicemail. Clear guidance at launch prevents missed calls and avoids employees falling back on personal mobiles.
Costs: look beyond the licence price
A like-for-like price comparison with an old telephone system can be misleading. Teams Phone costs may include Microsoft licensing, calling services, direct routing or operator charges, number porting, desk phones or headsets, professional setup and ongoing support.
The commercial case can still be compelling, especially where it reduces separate mobile, conferencing and phone-system costs. The benefit is not only a lower monthly figure. It can be simpler administration, fewer duplicate tools and a consistent service for a distributed workforce.
But cost should be measured against your actual usage. A business with predominantly UK calls and modest volumes has different requirements from one with international offices, customer service teams or frequent outbound calling. Ask for clarity on call bundles, overage rates, contract terms, hardware replacement and support responsibilities.
It is also sensible to distinguish between the platform and the service wrapped around it. Microsoft provides the technology, but a managed provider can design call flows, port numbers, configure policies, monitor service quality and provide a human point of contact when users need help. That operational layer often determines whether a new phone system feels straightforward or becomes another item for an overstretched internal team to manage.
A practical checklist for a Teams Phone deployment
Before committing, document the numbers you need to keep, the people who answer calls, your opening hours and your essential call routes. Include edge cases such as lone workers, overnight voicemail, holiday cover, temporary staff and escalations to senior managers. These are often missed during a basic demonstration.
Next, assess the network and devices. Headsets may be sufficient for many users, while reception teams, warehouse staff and meeting rooms may need different equipment. Test calls from the locations where employees actually work, not just from a well-connected office desk.
Plan number porting carefully. Moving existing numbers can take time and requires accurate information from the current provider. A staged rollout can reduce risk: pilot the service with a department, refine routing and user training, then move the wider organisation once the process is proven.
Finally, agree what support looks like after go-live. Who changes a call queue when an employee moves role? Who investigates a poor-quality call? Who helps if a new starter cannot receive external calls? Businesses should expect clear ownership, response expectations and regular reviews of whether the setup still suits how they operate.
Is Teams Phone right for your business?
Teams Phone is a strong choice for organisations that are invested in Microsoft 365, want a flexible cloud calling service and need staff to work consistently across office, home and mobile locations. It is particularly effective when call routing is relatively straightforward and the business values having communication tools in one place.
It may need additional design or complementary technology where reception handling is complex, call volumes are high or customer-service reporting is central to the operation. There is no disadvantage in recognising those needs early. A phone system should fit the way your business serves customers, rather than forcing staff to work around its limitations.
At Blowfish Technology, we see the best outcomes when telephony is treated as part of the wider IT estate, not a standalone purchase. The right decision considers the people taking calls, the network carrying them and the support behind them. Start with the customer journey you want every caller to experience, then choose the Teams Phone design that can deliver it reliably.
The Blowfish Technology team. Managed IT, cloud services, software development and connectivity for North West businesses since 1999.