The Complete Guide to PSTN Calling with Microsoft Teams

Microsoft Teams Phone has enabled seamless collaboration and connectivity since its launch in 2020. While many organizations choose to use Microsoft Teams Phone out of the box via calling plans, many also choose to enhance their Teams experience by using Operator Connect or Direct Routing. These newer connectivity options can help businesses save costs, enhance flexibility and global reach, and improve call quality and reliability.

Here we'll take a closer look at the different ways businesses can access Public Switched Telephone Network (PSTN) calling in Microsoft Teams so you can choose the best option for your business.

You can choose from a number of Microsoft-approved Operators to run Operator Connect or Direct Routing. However, some providers offer stronger platforms, tools, and networks than others. For instance, by using Telnyx’s robust PSTN services, your organization can enjoy unmatched flexibility, cost savings, and reliable calls, all via our private global network.

What is Microsoft Teams Phone?

Microsoft Teams Phone enables organizations to use Microsoft Teams as their primary phone system. This native calling solution enables users to make and receive phone calls easily through the Teams console for seamless communication.

For small companies who need PSTN calling through Teams infrequently, the calling plans from Microsoft are likely easiest to set up and will serve most business needs. However, there are other options for companies who are looking to optimize on costs, enhance their calling experience, and need coverage in countries outside of North America.

What is Direct Routing?

[Direct Routing] (https://telnyx.com/resources/direct-routing-overview) for Microsoft Teams enables businesses to connect their own telephony services to Microsoft Teams, allowing users to make and receive external calls to and from the PSTN.

Direct Routing provides the most flexibility of the three calling options by integrating existing SIP trunks or telephony providers with Teams. It is also capable of supporting complex telephony configurations, making it suitable for organizations with specific telephony needs.

Direct Routing requires the use of a Microsoft-certified Session Border Controller (SBC) to route calls between Teams and the PSTN.

What is Operator Connect?

Launched in 2021 as an evolution of Direct Routing, Operator Connect simplifies the integration of third-party PSTN services with Microsoft Teams. Unlike Direct Routing, Operator Connect requires minimal configuration and can be managed through the Teams admin portal.

Operator Connect’s ability to consolidate internal communications infrastructure efficiently makes it an ideal choice for organizations seeking a quick, straightforward setup. Due to the simple integration, businesses have less control over their call routing, making it suitable for small-medium organizations with basic telephony needs.

Operator Connect vs. Direct Routing

You can use the table below as a quick comparison between Operator Connect and Direct Routing. We’ll go into more detail about each of these components later on in our guide.

Ideal customers for Direct Routing and Operator Connect

Who should use Direct Routing?

Direct Routing is ideal for larger organizations that need to integrate legacy PBX systems with Microsoft Teams. It supports analog phones and other traditional telephony devices, making it perfect for businesses that still rely on these technologies.

Direct Routing is also the best option for companies operating globally, in many countries outside of the markets supported in on Microsoft Teams Calling Plans. Direct Routing provides greater flexibility in choosing telecom providers—many companies are able to use their existing SIP Trunking provider for PSTN calling in Teams. This allows organizations to leverage existing telephony investments while ensuring seamless integration with the modern capabilities of Microsoft Teams.

These factors make it a great solution for enterprises with specific telephony requirements in multiple markets, advanced routing needs, and the technical expertise to manage a more complex setup.

Who should use Operator Connect?

Operator Connect is ideal for cloud-first organizations that prioritize easy integration with Microsoft Teams and minimal on-premises infrastructure. It’s also perfect for remote work environments, providing seamless connectivity for employees who rely on modern calling devices such as smartphones and laptops.

This solution is designed for businesses that value quick deployment and simplified management, so IT teams don't have to worry about maintaining complex telephony systems. Operator Connect also offers robust support and service level agreements (SLAs), making it an attractive choice for companies seeking reliability and ease of use.

Limitations of Direct Routing and Operator Connect

Direct Routing limitations

Direct Routing offers greater flexibility and customization, but requires more technical expertise and resources to set up and maintain. Managing SBCs and integrating them with existing telephony systems can be challenging for organizations without dedicated IT staff.

While Direct Routing provides extensive control and customization, this level of detail may be unnecessary for smaller businesses or those seeking a simpler setup. Additionally, ongoing management and troubleshooting can be resource-intensive, making it less appealing for organizations looking for a low-maintenance solution.

Operator Connect limitations

While Operator Connect is easy to set up and manage, it’s limited by its reliance on certified operators, which restrict the choice of providers for businesses. This restriction can lead to higher costs if competitive pricing is unavailable in certain regions. It also lacks the flexibility to integrate with legacy systems or analog devices, making it less suitable for organizations with existing telephony infrastructure.

Additionally, Operator Connect may not cover all countries, limiting its global reach for businesses operating in less common regions. Finally, the control over routing and advanced telephony features is less granular compared to Direct Routing.

Setup needs for Direct Routing and Operator Connect

Direct Routing setup

Direct Routing offers greater control over the telephony environment than Operator Connect. It also allows for customized routing policies and integration with existing systems. However, it requires a higher level of technical expertise and involvement to configure versus Operator Connect, which can be setup by an MS Teams admin. The more detailed configuration required by Direct Routing includes:

• SBCs—either on-premise or in the cloud—to connect existing telephony infrastructure to Microsoft Teams.
• SIP trunk setup.
• Continuous management of the telephony components.

Operator Connect setup

Operator Connect is designed to be straightforward and easy to set up, requiring minimal technical expertise. It involves selecting a certified operator from within the Microsoft Teams admin center and following simple prompts to connect and manage phone numbers. The operator handles the majority of the infrastructure, including Session Border Controllers (SBCs), making the process quick and user-friendly.

This approach reduces the need for in-depth technical knowledge or additional hardware, allowing for faster deployment and management.

Required licenses for Direct Routing and Operator Connect

Required Microsoft licenses for Direct Routing

Direct Routing requires users to have Microsoft Teams licenses that include the Phone System add-on. This add-on is essential for enabling calling capabilities within Teams.

Beyond these licenses, organizations need to ensure they have licenses for any additional components they may use, such as SBCs. Users assigned phone numbers through Direct Routing need appropriate licenses to handle PSTN calls.

This setup often involves a more complex licensing structure due to the need to integrate with existing telephony systems and infrastructure. The comprehensive control and customization offered by Direct Routing come with the necessity for more detailed licensing management.

Required Microsoft licenses for Operator Connect

Operator Connect requires users to have the same licenses as Direct Routing, except for the SBC license. Businesses also need to ensure they have sufficient user licenses for those who will be assigned phone numbers through Operator Connect. These licenses allow users to make and receive calls within the Teams environment, leveraging the operator-managed PSTN connectivity.

The simplicity of this licensing model aligns with the overall ease of setup and management that Operator Connect offers.

• M365 or O365 user license
• Teams Phone System license (included in E5 user license)

Cost associated with Direct Routing and Operator Connect

Direct Routing costs

Direct Routing can involve higher upfront costs because it often requires the purchase and setup of associated infrastructure such as SBCs, however some vendors, like Telnyx, do not charge for SBC configuration, reducing set-up and infrastructure costs. Organizations also need Microsoft Teams licenses with Phone System add-ons, but Direct Routing customers can benefit from the flexibility to choose their existing telephony provider, which can lead to more competitive calling rates.

Direct Routing is usually based on pay-as-you-go pricing which often offers long-term savings over calling plans and Operator Connect through reduced call charges and the ability to integrate with existing telephony infrastructure.

Operator Connect costs

Operator Connect generally involves low upfront costs due to its straightforward setup, which doesn't require additional hardware or significant technical expertise. The primary expenses are related to the Microsoft Teams licenses with Phone System add-ons and the service fees from the chosen operator.

Operator Connect is usually sold through bundles from carriers. This model provides predictable, subscription-based pricing, making budgeting easier. However, the reliance on certified operators can sometimes lead to higher recurring costs compared to a fully self-managed solution.

Additional MS Teams calling features

When setting up either Operator Connect or Direct Routing, there are several additional features you should consider. Here are the primary things you should consider when choosing either Operator Connect or Direct Routing for MS Teams Phone calling:

Emergency addresses support

Both Direct Routing and Operator Connect require accurate emergency addresses for E911 compliance. Each end-user’s location should be up-to-date to enable precise routing of emergency calls. This setup is crucial for regulatory compliance and user safety, ensuring emergency services can respond promptly and accurately.

Auto attendant

An auto attendant in Microsoft Teams allows callers to navigate a menu system to reach the appropriate department, person, or resource within an organization. It can route calls based on input to destinations such as an operator, individual, voicemail, another auto attendant, or external numbers. Auto attendants can also play announcements and handle after-hours and holiday call flows.

Auto attendant configuration involves setting up general information, call flows, dial scope, resource accounts, and authorized users.

Voicemail

Both Direct Routing and Operator Connect support Microsoft Teams voicemail integration. Ensure users are properly licensed and configured within Teams to access voicemail features. Voicemail settings and management are handled within the Teams admin center, providing a consistent experience across both connection methods.

Porting numbers

Porting numbers to Telnyx for both Operator Connect and Direct Routing requires submitting a port request via the Telnyx portal. Ensure all required documentation is accurate to avoid delays. The process typically includes validation, authorization, and coordination with your current provider to ensure a smooth transition.

Microsoft Teams Phone integration provider considerations

In addition to features and capabilities, there are a few main factors you should consider when choosing an Operator Connect or Direct Routing provider:

Global presence

The support range for approved Microsoft Operators varies. To understand which countries your provider of choice supports, check the Teams Admin Center Operator list.

It’s also essential to know if your provider is a carrier or a licensed reseller, as this can affect their service capabilities in a given country. For instance, licensed resellers may provide limited abilities to resell those same services to your own customers. Direct carriers don’t experience this issue.

Support and troubleshooting

Choosing a provider with expert support is crucial for both Operator Connect and Direct Routing. Since you’re using a third-party solution to run your Voice infrastructure, you'll want to choose an experienced operator or channel partner to manage your services effectively.

Comprehensive support is essential for seamless integration and ongoing management, helping to prevent problems and streamline the setup process. Opting for a provider with expertise and cost-effective support can significantly enhance the overall experience and reliability of your PSTN integration.

Voice network quality

Not all Operator networks are equally powerful. To ensure low latency, high-quality calls, you should prioritize a provider that offers global coverage on a fast network.

Advanced configuration

Now that we’ve covered the basics, it’s time to address advanced features and tools you should consider in your Direct Routing or Operator Connect setup.

Shared calling

Shared calling allows multiple users to share one number. This configuration helps organizations save money by charging per number instead of per user, creating an opportunity to provide cost-effective team communication.

Desk phones

For Operator Connect, supported desk phones can seamlessly integrate with Microsoft Teams, enhancing office communication. Direct Routing allows users to connect almost any device - even analog phones - via certified SBCs which support traditional telephony devices. These configurations ensure versatile and robust desk phone integration within Teams.

Mobile device integration

Teams Phone Mobile enables users to use their SIM-enabled phone number as their Teams number, enabling seamless integration. Operator Connect also supports mobile devices, ensuring consistent communication across platforms. This advanced configuration enhances mobility and flexibility for users.

SMS integration

Integrating SMS with Operator Connect and Direct Routing enhances communication capabilities. Some third-party solutions offer seamless SMS integration with Microsoft Teams, allowing users to send and receive SMS directly within the Teams environment. This feature supports efficient messaging without leaving the Teams interface.

Call forwarding

Call forwarding ensures calls aren’t missed when a user is unavailable. Both Operator Connect and Direct Routing support this feature. You can set up call forwarding easily through Microsoft Teams settings, enhancing flexibility and availability for users.

Choose Telnyx as your PSTN provider for Microsoft Teams Phone

Using Telnyx PSTN services with Microsoft Teams through Operator Connect and Direct Routing offers flexible and robust solutions to meet your organization's communication needs. Whether you need the simplicity of Operator Connect or the flexibility of Direct Routing, Telnyx provides the expertise and support to ensure a seamless integration.

Choosing the right PSTN provider is crucial for seamless and reliable communication. Integrating Telnyx with Microsoft Teams Voice through Operator Connect or Direct Routing offers businesses a powerful, flexible, and cost-effective solution for their communication needs.

By opting for Telnyx, you benefit from competitive pricing, flexible solutions, and a dedicated support team ready to assist with any challenges. Whether you’re a cloud-first organization looking for easy integration or a company with existing telephony infrastructure needing advanced customization, Telnyx provides the necessary tools and support to enhance your Teams experience.