Configuring Microsoft Teams SIP Gateway for SIP Phones

Summary 

In the first blog, we covered the overview and objective of testing Microsoft Teams Phone with third-party SIP devices, including the Fanvil A320 and a Yealink SIP phone. This second blog focuses on the complete Microsoft Teams SIP Gateway setup, including provisioning steps, troubleshooting, network requirements, and important deployment lessons learned during testing. 

The goal of this test was to determine whether a Microsoft Teams Phone number could be used on a SIP desk phone for a traditional VoIP calling experience. The results showed that Microsoft SIP Gateway provisioning worked successfully on the Yealink SIP phone, while the same process did not work on the Fanvil A320 because the device is not included in Microsoft’s list of compatible SIP Gateway devices. 

Test Environment(Table) 

High-Level Microsoft Teams SIP Gateway Configuration Flow (Keep it in a box) 

The Teams SIP Gateway setup followed this process: 

Teams Admin Center
        ↓
Enable SIP devices in Calling Policy
        ↓
Confirm Teams Phone license and phone number
        ↓
Factory reset SIP phone
        ↓
Configure Microsoft SIP Gateway provisioning URL
        ↓
Reboot phone
        ↓
Phone displays Microsoft sign-in option
        ↓
Sign in using Teams user account
        ↓
Validate inbound and outbound calling
 

Step 1: Prepare the Microsoft Teams User Account 

Before starting the Microsoft Teams SIP phone configuration, the Teams account must be fully prepared for calling. 

The account used for sign-in must have: 

• A valid Microsoft Teams license 

• A Teams Phone license 

• A phone number assigned to the user 

• A Teams calling policy that allows SIP devices 

• PSTN calling enabled through Calling Plan, Operator Connect, or Direct Routing 

One important lesson during testing was that the SIP phone should not be signed in using a random admin account unless that account owns the assigned Teams phone number. The account used during Microsoft device provisioning must match the user expected to make and receive calls on the desk phone. 

Step 2: Enable SIP Devices in Teams Admin Center 

The next step in the Microsoft Teams SIP Gateway setup was enabling SIP devices in the Teams calling policy. 

In the Teams Admin Center, navigate to: 

Teams Admin Center → Voice → Calling policies
 

Enable the following setting: 

SIP devices can be used for calls = On
 

This setting must be enabled in the calling policy assigned to the Teams user. If a custom policy is assigned, the setting must be enabled there. If the user inherits the global policy, the global policy must be updated. 

A common issue during Teams SIP device configuration is assuming policy changes apply instantly. In many environments, policy propagation may take time across the Microsoft 365 tenant. If the phone does not immediately show the Microsoft sign-in option, wait and retry after some time. 

Step 3: Factory Reset the SIP Phone 

Factory reset was an important step before beginning SIP Gateway provisioning. 

Resetting the SIP phone removes old SIP profiles, cached provisioning settings, and previous VoIP configurations that could interfere with the Microsoft Teams provisioning process. 

General reset process: 

Phone Menu → Settings → Factory Reset
 

After the reset, no manual SIP account configuration was added. This is important because Microsoft SIP Gateway does not use traditional SIP registration details such as SIP username, registrar, proxy, or password fields. 

Step 4: Configure the Microsoft SIP Gateway Provisioning URL 

After the factory reset, the phone was configured to connect to Microsoft’s SIP Gateway provisioning service. 

For North America, the provisioning URL used was: 

http://noam.ipp.sdg.teams.microsoft.com
 

Other regional provisioning URLs include: 

• EMEA 

http://emea.ipp.sdg.teams.microsoft.com
 

• APAC 

http://apac.ipp.sdg.teams.microsoft.com
 

On the SIP phone, this URL must be added under the phone’s Auto Provisioning or Provisioning Server settings. 

Recommended SIP Provisioning Settings(Table) 

A major takeaway from this Microsoft Teams VoIP setup is that Microsoft Teams SIP Gateway does not work like a standard VoIP provider. Microsoft does not provide SIP usernames or passwords for Teams Phone numbers. Instead, provisioning is completed through Microsoft authentication and device sign-in. 

Step 5: Reboot and Wait for Microsoft Sign-In 

After saving the provisioning URL, reboot the SIP phone. 

If provisioning is successful, the phone displays a Microsoft sign-in option or device code. This confirms that the phone has successfully connected to the Microsoft Teams SIP Gateway and is ready for user authentication. 

The Yealink SIP phone successfully completed this stage, confirming compatibility with Microsoft SIP Gateway. 

The Fanvil A320 did not complete the provisioning process successfully because the device is not listed among Microsoft’s compatible SIP Gateway devices. 

Step 6: Complete Microsoft Device Sign-In 

Once the phone displayed the sign-in prompt, device registration was completed through the Microsoft provisioning portal: 

https://aka.ms/deviceprovisioning
 

Use the Teams user account assigned to the phone number. 

After entering the device code and signing in, the phone successfully registered with Microsoft Teams Phone and became associated with the assigned user account. 

Recommended Microsoft Teams SIP Gateway Checklist(Table) 

Before starting Teams SIP Gateway provisioning, use this checklist: 

Key Learnings 

• Microsoft SIP Gateway Is DifferentFromTraditional SIP Registration 

Microsoft Teams SIP Gateway does not function like a standard SIP provider. There are no manual SIP credentials or registrar settings entered into the phone. Instead, the process relies on Microsoft provisioning and device authentication. 

• Device Compatibility Is Critical

The Yealink SIP phone worked successfully because it supports Microsoft Teams SIP Gateway. The Fanvil A320 failed because it is not included in Microsoft’s supported SIP device list. 

• Factory Reset Prevents Provisioning Conflicts

Factory reset removed old SIP configurations and provisioning remnants, creating a clean environment for Teams SIP device configuration. 

• Network Readiness Is Essential

Even with the correct provisioning URL and supported device, DNS issues, firewall restrictions, or proxy settings can prevent successful SIP Gateway provisioning. 

• Teams App Calling and SIP Gateway Calling Are Different

The Fanvil A320 was able to run the Microsoft Teams Android app after a firmware update, but that does not make it a true SIP Gateway-compatible desk phone. Teams app calling behaves differently from a dedicated Microsoft Teams VoIP phone experience delivered through SIP Gateway. 

References 

• Plan SIP Gateway – Microsoft Teams | Microsoft Learn 

• Configure SIP Gateway – Microsoft Teams | Microsoft Learn 

• Common Issues Using SIP Devices With Teams – Microsoft Learn