Microsoft Teams is already in your office — here's why it should replace your phone system too

If your business subscribes to Microsoft 365, there is a good chance every single one of your staff already has Microsoft Teams installed. They use it for chat. They use it for video meetings. They share files through it. And yet, sitting on a shelf in your comms room or mounted on every desk, there is still a separate phone system doing a completely different job.

That separation made sense once. It does not anymore. Voice calling in Teams is one licence add-on away — and once it is enabled, you have a complete, enterprise-grade phone system built directly into the tool your team already uses every day.

What "Teams calling" actually means

Microsoft Teams has always been able to handle calls between users within your organisation — internal calls are free and built in. What Microsoft Teams Calling adds is the ability to make and receive calls to and from regular phone numbers: landlines, mobiles, other businesses, customers. Your existing business numbers get ported across, and from that point on, Teams is your phone system.

The technical side of how calls are connected to the public telephone network is handled either through Microsoft's own Calling Plans or through a telco like Caznet using a method called Direct Routing. The end result for your staff is identical either way — they pick up a call in Teams the same way they would open a chat.

One app for everything

This is where the business case becomes obvious. Today, a typical office worker might switch between:

• Teams or Slack for internal messaging
• Teams or Zoom for video meetings
• A desk phone or softphone for external calls
• Outlook for email and calendar

With Teams Calling enabled, the desk phone disappears. External calls come through the same Teams interface. Presence status — whether someone is available, in a meeting, or on a call — is accurate across all of those contexts automatically. When a colleague is shown as "In a call," they are actually in a call, whether that is an external phone call or an internal Teams meeting.

The integration with Outlook calendar is particularly useful. Meeting blocks automatically update your presence. Calls can be initiated directly from a contact card. Call history sits alongside your chat history. It is unified communications in the truest sense.

No hardware refresh required

Traditional PBX systems are tied to physical hardware. When that hardware reaches end of life — typically every seven to ten years — you face a significant capital outlay to replace it. In between, you pay annual maintenance fees just to keep it supported.

Teams Calling eliminates that cycle entirely. The "system" is software running in Microsoft's cloud. Updates happen automatically. There is no server to maintain, no proprietary hardware to replace, and no firmware to patch. If your staff already have computers and headsets — or even just their mobile phones with the Teams app — you may not need to purchase a single piece of new equipment.

For businesses that do want a physical handset on the desk, there is a range of Teams-certified desk phones available. But they are optional, not mandatory.

Enterprise phone features included as standard

Teams Calling is not a stripped-back VoIP product. The feature set matches what you would expect from a dedicated business phone system:

• Auto-attendant: Callers hear a menu ("Press 1 for Sales, Press 2 for Support") and are routed accordingly, 24 hours a day.
• Call queues: Incoming calls wait in a queue and are distributed across available agents — useful for reception desks, support lines, or sales teams.
• Call recording: Record calls for compliance, training, or quality assurance. Recordings are stored in your Microsoft 365 environment.
• Voicemail with transcription: Voicemails are automatically transcribed and delivered to your email inbox.
• Call transfer and hold: Blind transfer, attended transfer, and call hold work exactly as they do on a traditional phone system.
• Call from any device: Desktop app, mobile app, web browser — your business number follows you, not your desk.

How it compares to a traditional PBX

A traditional PBX does one thing: route phone calls. It does that job reliably, and for businesses that have had the same system for a decade, it can feel like a solved problem. But the comparison starts to look less favourable when you factor in what you are not getting.

A PBX has no awareness of your calendar. It cannot tell whether someone is genuinely available or in a meeting. Moving an extension to a new desk requires a technician visit. Adding a new user means provisioning a physical phone and potentially running new cabling. And when your staff work from home or travel, the desk phone stays behind.

Teams Calling handles all of those scenarios natively. A new staff member downloads the app, is assigned a number, and is ready to make and receive calls within minutes. A remote worker has exactly the same experience as someone sitting in the office.

For businesses already running Microsoft 365, replacing an aging PBX with Teams Calling is often the most logical path forward. And for businesses that prefer a dedicated cloud phone system without the Microsoft dependency, a cloud PBX achieves similar results with even more flexibility in handset and feature choices.

Who is it the right fit for?

Teams Calling suits businesses that:

• Are already on Microsoft 365 and want to consolidate their tools
• Have staff who work remotely, in multiple locations, or frequently travel
• Are approaching a PBX hardware refresh and want to avoid another capital outlay
• Want call recording, auto-attendant, and call queues without paying for additional software
• Value having a single vendor relationship for productivity and communications

It is less suited to businesses with very specialised telephony integrations — certain contact centre platforms, for example — though Microsoft's Teams ecosystem has expanded considerably in that space as well.

Getting set up with Teams Calling in Adelaide

The practical steps involve assigning Phone System licences in your Microsoft 365 admin portal, choosing how calls will connect to the public network (Calling Plans or Direct Routing), porting your existing numbers, and configuring auto-attendants and call queues to match your current setup.

Caznet handles the Direct Routing connection and number porting for Adelaide businesses — which means you keep your existing local numbers and call rates remain competitive. The transition from a traditional system can typically be completed with no downtime and minimal disruption to your team.

If you are already paying for Microsoft 365, the real question is not whether Teams can replace your phone system. It is why you have not done it yet.