Knowledge base

December 14, 2025

Microsoft Teams as a full-fledged phone system?

 

More and more organizations are using Microsoft Teams to make calls. It makes sense, too. You use one platform for chat, video conferencing and telephony. No more separate PBX. No additional apps. Just work from Teams, in the office, at home or on the road.

But is Teams really suitable as a full-fledged phone system? The short answer: yes, provided you set it up properly. In this article you will read how Teams Telephony works, what you need and what to consider in the Netherlands.

What is Teams Telephony?

With Teams Telephony, you call through Microsoft Teams as if it were your landline phone. You can receive calls on a landline number, make outgoing calls and transfer calls. Everything runs through your Microsoft 365 environment.

Your employees make calls from their laptops, headsets, smartphones or desktops. It doesn’t matter where they work. That makes Teams Telephony suitable for hybrid organizations and growing teams.

Linking teams to your landline number: two options

To make calls with Teams, you need a connection to the public telephone network. There are two ways to do this.

 

Direct Routing: maximum control

 

With Direct Routing, you link Teams to your own SIP trunk. This gives a lot of flexibility.

You choose your own telecom provider.
You have full control over numbering plans and routing.
Integration with existing telephony is possible.

This option does require technical management and a secure infrastructure. This is often set up through a specialized partner.

 

Operator Connect: simplicity and speed

 

With Operator Connect, you arrange everything through a certified provider directly in Teams.

No proprietary SBC required.
Rapid implementation.
Management largely through Microsoft.

This is a low-cost option for organizations that want to get started quickly and want less technical management.

 

What do you need to get started?

 

Teams Telephony doesn’t work by itself. These are the basic requirements.

  • One Microsoft Teams Phone license per user.
  • A fixed 088 number or number block. This can be an existing number or a new number.
  • A secure connection via certified infrastructure. Think encryption, redundancy and monitoring.

In addition, proper setup is important. Consider call groups, opening hours, voicemail and emergency numbers.

 

Important in the Netherlands: compliance and regulation

 

Telephony touches directly on legislation. Especially if you record calls or work in regulated industries.

  • Number recognition and reachability
  • Outgoing numbers must be displayed correctly. Anonymous or incorrect number display can lead to complaints or blocking. In the Netherlands, there are clear rules for this.
  • Call recordings and AVG

Are you recording conversations? Then you are processing personal data. Meaning:

  • Clear foundation and purpose.
  • Informing callers.
  • Limited retention periods.
  • Secure storage within the EU.

Without proper arrangements and setup, you run the risk of AVG violations.

 

Healthcare and government: additional requirements

 

Do you work in healthcare or for government organizations? Then NEN7510 is relevant. Teams Telephony must then fit within your information security policy. Think about access management, logging and incident handling.

 

Why Teams Telephony works well for hybrid working

 

Teams Telephony is scalable and flexible. You add new employees quickly. Temporary workers are easily assigned a number. Moving or expanding costs no additional hardware.

  • Employees are accessible on any device.
  • One workspace for communication.
  • Less management and lower costs.

The prerequisite is that the setup is right. Poor audio quality, unclear call paths or unsafe settings quickly create frustration.

Common mistakes in practice

We often see the same issues recurring.

  • Starting too soon without draft number plan.
  • No attention to compliance and retention periods.
  • Insufficient network check, resulting in poor call quality.
  • No fallback in case of outages or Internet downtime.
  • Teams Telephony works well, but not automatically. It requires a thoughtful approach.

 

How ALTA-ICT tackles Teams Telephony.

 

At ALTA-ICT, we look beyond technology. We start with your organization and processes.

  • We are taking stock of how calls are made now.
  • Together, we determine the best option: Direct Routing or Operator Connect.
  • We set up Teams Telephony securely according to Dutch legislation.
  • We test accessibility, quality and emergency scenarios.

Our approach is practical and tailored to Dutch organizations. With attention to AVG, NEN7510 and continuity.

 

Is Teams Telephony right for your organization?

 

Are you already using Teams for collaboration? Then the step to telephony makes sense. It provides overview and supports flexible working.

The question is not whether Teams Telephony can do it. The question is whether it is set up properly for your situation.

Are you already using Teams as your phone system or considering the switch? Feel free to send us a message if you would like to spar about the possibilities for Teams Telephony in your organization. We are happy to think along with you.

Want to know more?

Get in touch
Teams Telefonie Operator Connect 088 Nummer