Here's How We Make External Calls in Teams (+ Best Practices)

Businesses need a unified communications solution for internal and external calls. Fortunately, Microsoft Teams offers all the features of a traditional phone system (PBX) but with the added benefits of Teams' collaboration tools. It lets you make and receive external voice calls just like a regular business phone system. In this ZIRO guide, we'll walk you through how to make external calls in Teams, including the requirements and the steps involved.

What Are External Calls in Microsoft Teams?

External calls in Microsoft Teams refer to the ability to make and receive phone calls to and from traditional phone numbers (PSTN) using the Teams app. This functionality transforms Teams into a full-fledged telephony system, either managed internally or through third-party solutions like Direct Routing, Operator Connect, or Calling Plans. It allows users to communicate with people outside their organization, such as clients, partners, and customers.

What Do You Need To Make External Calls in Teams?

Microsoft Teams Phone System License

The first requirement is the appropriate license. Specifically, you'll need the Microsoft Teams Phone license, which allows Teams to make and receive calls over the PSTN. There are three main licensing options:

• Teams Phone Standard: Add-on license offering hosted telephone service with PBX capabilities. It allows you to connect to PSTN via various options, including choosing Microsoft as your PSTN carrier.
• Microsoft Teams Calling Plans: Add-on license for making PSTN calls with Microsoft as your carrier. Ideal if Calling Plans are available in your region.
• Teams Phone with Calling Plan Bundle: Combines Teams Phone and a Microsoft Calling Plan for PSTN connectivity, simplifying setup.

PSTN Connectivity Options

Once you have the phone system license, you'll need a way for Teams to route external calls to and from the public telephone network. You have four primary options:

• Calling Plan: Purchase a calling plan directly from Microsoft. However, this is only available in about 33 countries, and you may have less control over call routing options and costs.
• Teams Phone Mobile: Your SIM-enabled phone number doubles as your Teams phone number. If your carrier is part of the Microsoft Teams Phone Mobile program, they can handle PSTN calling for Teams.
• Direct Routing: Use your existing PSTN provider by connecting it to Teams through Direct Routing. This involves configuring a Session Border Controller (SBC) to connect SIP trunks to Microsoft Teams, which typically requires expert assistance from a service provider like ZIRO.
• Operator Connect: Microsoft works with selected operators to provide calling services, which can be easier to manage than Direct Routing, though with fewer customization options.

You can take advantage of our comprehensive Direct Routing as a Service (DRaaS) solution at ZIRO to set your PSTN connectivity up faster via Direct Routing, with lower risk and cost.

Other Requirements

• Phone Numbers: You'll need phone numbers assigned to your Teams users, obtainable via Microsoft (Calling Plan) or your telephony provider (Direct Routing or Operator Connect).
• Teams-Enabled Device or App: You can make external calls using a Teams-certified desk phone, mobile app, or desktop app.

How to Set Up External Calling in Microsoft Teams

Step 1: Assign Teams Phone Licenses

Assign Microsoft Teams Phone licenses via the Microsoft 365 Admin Center: navigate to the Microsoft 365 Admin Center, go to Users > Active users, then select the user and assign the appropriate Teams Phone license. You can do this individually or in bulk; PowerShell can automate bulk assignment.

Step 2: Set Up a PSTN Connectivity Option

If Using Microsoft Calling Plan: Log in to the Microsoft 365 Admin Center, navigate to Billing > Purchase Services, choose a calling plan (Domestic, International, or Pay-As-You-Go), then assign it to users via Teams Admin Center > Voice > Phone Numbers.

If Using Direct Routing: Configure a Session Border Controller (SBC) with your telephony provider to connect your SIP trunks to Teams; in the Teams Admin Center, go to Voice > Direct Routing and configure your SBC; then assign phone numbers from your PSTN provider. Additional read: Step-by-Step Guide to Microsoft Teams Direct Routing Configuration.

If Using Operator Connect: Open the Teams Admin Center, go to Voice > Operator Connect, choose a certified provider, follow their instructions to integrate, then assign phone numbers.

If Using Teams Phone Mobile: Work with a Teams Phone Mobile-certified carrier, configure Teams to route mobile calls through your carrier's network, then assign the mobile phone numbers to users.

Step 3: Assign Phone Numbers to Users

Go to the Teams Admin Center, navigate to Voice > Phone Numbers, and assign phone numbers to users so they can make and receive external calls.

Step 4: Make an External Call

Once setup is complete, open the Microsoft Teams app, go to the Calls tab on the left-hand side, and use the dial pad or search for an external number to make a call.

Best Practices for Making Microsoft Teams External Calls

• Optimize Call Quality: Use a stable, wired connection and Teams-certified devices like headsets. Regularly monitor network performance to minimize latency, packet loss, and jitter.
• Make Necessary Checks: If using Direct Routing or Operator Connect, verify routing configurations with your provider, and confirm the correct phone number is assigned in the Teams Admin Center.
• Improve User Experience: Train users on features like voicemail and call forwarding. Enable self-service options such as voicemail transcription.
• Secure External Calls: Activate multi-factor authentication (MFA) and call encryption. Regularly check call logs to detect potential security risks.
• Administer Call Policies: Set calling policies, such as limiting international calls or enabling delegation, and use the Teams Call Quality Dashboard to track and troubleshoot.
• Plan for Disaster Recovery: Have a backup plan for external calls in case of outages to keep mission-critical communication uninterrupted.

Simplify Your External Calling Setup in Teams with ZIRO

Even with a detailed guide like this, setting up Microsoft Teams for external calling can feel complex, but it doesn't have to be. At ZIRO, we specialize in simplifying Microsoft Teams Voice migrations by handling everything from start to finish. Whether you're configuring a Calling Plan, Direct Routing, or Operator Connect, we ensure the entire process is fast, smooth, and risk-free. Contact us today to get started.