In today’s digital-first workplace, communication is no longer just about making calls. It’s about creating seamless, connected experiences across voice, video, messaging, collaboration, and workflow automation. Microsoft Teams has quickly become the centerpiece of enterprise collaboration, integrating chat, meetings, and file sharing into a single hub. But when it comes to extending Teams into a full unified communications platform with voice and telephony, businesses face several key choices: Microsoft Teams Dial Plans, Direct Routing with SIP trunks and SBCs, or Operator Connect.

At CIS, we work with businesses of all sizes to help them navigate these choices, design the right architecture, and integrate Microsoft Teams into a broader UCaaS or CCaaS strategy. As I’ve been exploring opportunities with innovative organizations like Xperi, it’s clear that forward-thinking enterprises are seeking solutions that not only enable communication but also enhance collaboration, security, and the customer experience on a global scale.

Microsoft 365 as the Foundation of UC

Before diving into telephony, let’s zoom out and look at why Microsoft Teams is so powerful in the first place. It’s not just a meetings app—it’s part of the broader Microsoft 365 ecosystem.

• Microsoft Exchange & Outlook: Business email and calendars that sync natively with Teams meetings.
• SharePoint & OneDrive: Centralized file storage with version control and collaboration baked in.
• Azure Active Directory: Single sign-on and identity management to keep users secure.
• Copilot (AI Integration): Microsoft’s AI layer that brings productivity intelligence into Teams chats, emails, and documents.
• Power Platform: Low-code apps, workflows, and automation that can connect Teams with other business systems.

Together, these components make Teams the “front door” for collaboration, while the Microsoft 365 + Azure stack ensures scalability, compliance, and security. However, once you add voice to the mix, you need to decide how to connect Teams to the public switched telephone network (PSTN).

Microsoft Teams Voice: Three Options

1. Microsoft Calling Plans (Dial Plans)

This is the simplest option—Microsoft becomes your phone carrier. You purchase user licenses that include calling minutes and phone numbers directly from Microsoft.

Pros:

• Easy to set up, no SBC required.
• One vendor (Microsoft) for everything.
• Best for small to mid-sized businesses with straightforward needs.

Cons:

• Limited coverage in certain countries.
• Less flexibility in carrier pricing.
• Less control for enterprises with complex telephony requirements.

When to use it: If you’re a smaller business (20–200 employees) that wants quick, no-friction telephony integration into Teams without managing infrastructure.

2. Direct Routing (SIP Trunks + SBC)

Direct Routing connects Teams to the PSTN through your own SIP trunk provider via a Session Border Controller (SBC).

Pros:

• Full flexibility—choose your carrier, negotiate rates.
• Enterprise-grade control over call routing, redundancy, and failover.
• Useful for integrating legacy PBXs or call centers alongside Teams.

Cons:

• Requires more expertise to configure and manage.
• SBC hardware/software adds cost.
• More moving parts, so vendor coordination matters.

When to use it: Mid to large enterprises (250+ users) that want full control, global coverage, and the ability to blend Teams with existing UCaaS/CCaaS platforms.

3. Operator Connect

Operator Connect is a middle ground: Microsoft-certified carriers provide PSTN connectivity that plugs directly into Teams, no SBC required on your end.

Pros:

• Easier than Direct Routing, more flexible than Dial Plans.
• Carriers handle the heavy lifting—porting numbers, failover, and regulatory compliance.
• Ideal for distributed, global organizations.

Cons:

• Limited to carriers that participate in the Operator Connect program.
• Less customizable than full Direct Routing.

When to use it: Enterprises that want fast, reliable voice integration without managing SBCs but still need global reach.

SBC vs Operator Connect: Which is Right for You?

This often comes down to control vs simplicity:

• SBC (Direct Routing) → You control carriers, routing, and integrations. Better for complex, regulated, or global companies.
• Operator Connect → The carrier controls the PSTN connectivity, reducing complexity. Better for enterprises that want reliability without a heavy internal IT lift.

At CIS, we often recommend Direct Routing for companies with call centers, hybrid infrastructures, or international calling complexity, while Operator Connect works well for fast-growing organizations that want predictable, scalable voice without managing an SBC footprint.

Teams + Zoom: When to Use Which

While Teams is excellent for internal collaboration (chat, meetings, file sharing), some organizations also rely on Zoom—especially for external, global conferencing.

For example, enterprises like Xperi with offshore development and operations teams may find Zoom’s cross-border reliability and familiarity useful for large-scale webinars or international town halls, while Teams remains the primary hub for day-to-day internal collaboration.

Best Practice:

• Use Teams for internal communication, project collaboration, and voice integration.
• Use Zoom for customer-facing webinars, training, or when offshore teams require interoperability with external vendors or partners.

Both can coexist when managed strategically, with integrations through Microsoft 365 and identity federation (Azure AD).

Why Enterprises Choose a UC Partner

Unified Communications projects aren’t just about the tech—they’re about design, deployment, adoption, and support. That’s where a UC partner like CIS adds value:

• Strategy & Design: Choosing between Dial Plans, Direct Routing, or Operator Connect.
• Vendor Management: Negotiating SIP trunks, managing SBCs, or aligning carriers.
• Implementation: Configuring Teams, Exchange, and security policies in Azure.
• Adoption: Training users on Teams, Copilot, file sharing, and hybrid workflows.
• Post-Support: Troubleshooting voice quality, integrating APIs, optimizing AI/analytics.

This is especially critical for enterprises that operate globally, where workforce management (WFM), customer experience (CX), and AI-driven insights all intersect.

CIS + Forward-Looking Enterprises

At CIS, we’re passionate about helping businesses scale communication without adding complexity. I’ve seen how organizations like Xperi are pushing the boundaries of innovation—integrating Teams with global operations, balancing collaboration with customer experience, and exploring AI-driven productivity with Microsoft Copilot.

Our role is to make sure the foundation of Unified Communications is secure, scalable, and future-ready. Whether that’s Direct Routing for full control, Operator Connect for ease, or hybrid integrations with Zoom for offshore collaboration, we help businesses choose the right path.

Final Thoughts

Microsoft Teams isn’t just a chat app—it’s a platform for building a unified, intelligent communications strategy. The key decisions—Dial Plans vs Direct Routing vs Operator Connect, SBC vs carrier-managed, Teams vs Zoom—depend on your company’s size, complexity, and global footprint.

For SMBs, Microsoft Calling Plans may be enough. For global enterprises like Xperi, a mix of Direct Routing or Operator Connect, AI-driven tools like Copilot, and hybrid conferencing strategies may be the winning formula.

At CIS, our mission is to guide businesses through these choices so they can unlock the full value of their Microsoft 365 and UCaaS investments.

Because at the end of the day, Unified Communications isn’t just about technology—it’s about how people connect, collaborate, and create impact.

Ready to modernize your business communications with Microsoft Teams and CIS? Schedule a consultation today and discover how we can simplify your voice, collaboration, and customer experience strategy.