You’re considering migrating to Microsoft Teams voice and you’ve got an idea of what your future telephony looks like.

But, as they say, it’s about the journey; not the destination. 

Depending on the size, complexity, and existing setup of your business, there are varying levels of difficulty when it comes to migrating to Microsoft Teams voice.

In this guide, we break down the major stage gates to move through before you push the button on your Teams Phone implementation.

1. Audit existing products and services

Since you installed your current PBX or turned on your cloud telephony service, there’s a good chance that multiple administrators have worked on it/owned it. 

If you’re one of those organizations, it can be eye opening of how much drift has happened within the system. 

There may be:

  • Old extensions
  • Trunks
  • Hunt groups
  • Custom routing tables

that are no longer being used. Without a full audit of the system, it is tough to know what needs to be moved and what needs to be pruned.

Utilizing automated tools, like Univonix, to do a discovery and gap analysis of the existing platform can speed the migration along by giving you an idea of what can be done quickly and what doesn’t need to be brought forward.

“Univonix is working out to be a great tool. Trying to do a large migration without it would be much more challenging.” – Director of IT Infrastructure, State/Local Government.

2. Audit existing users

As well as global or departmental configurations, specific users may have their own nuances. It may also be the case that you’ve retained setups for users who no longer work at your company.

It’s common here that due to a lack of automated number management, best practice was to leave everything live. Now is the chance to review what you have saved and cleanse your phone system data before you migrate to Teams voice.

After all, the quality of what goes in impacts the quality of what comes out. 

Start by checking activity on old extensions, dialing the number if there’s no activity, and gradually removing phone system configurations that don’t need migrating over.

Before you go further: Book your Teams Phone proof of value here

3. Design and planning

When moving to Teams voice for the first time, it’s not just rip and replace. The beauty of migrating to Teams voice is that you get to define new ways of working and communicating.

While a traditional phone system migration would usually revolve around ensuring feature parity (and you can still do this to an extent), designing your Teams voice experience incorporates leaving legacy functionality behind—in favor of embracing things like asynchronous communication and replacement cloud features.

AspectTraditional PBXMicrosoft Teams Voice
Migration ApproachFeature parity-focusedOpportunity to redesign communication workflows
Communication StylePrimarily synchronous (calls, voicemails)Embraces asynchronous tools (chat, channels, shared docs)
Hardware DependencyDesk phones, on-premise serversCloud-based, device-agnostic (PCs, mobiles, headsets)
User ExperienceFixed call routing, limited flexibilityDynamic call handling, presence-based routing, integrated with collaboration tools
Feature SetLegacy features like call parking, pagingModern features like auto-attendants, call queues, transcription, and analytics
Scalability & MaintenanceRequires manual upgrades and physical infrastructureScales with your Microsoft 365 environment, minimal maintenance
IntegrationLimited to hardwareDeep integration with Microsoft 365 apps (Outlook, SharePoint, OneDrive, etc.)

You may still need to prepare for PBX feature parity if your business relies on PSTN calling. Here’s what to check for, using a Cisco UCM PBX as an example:

Feature CategoryCisco UCM (Call Manager)Microsoft Teams PhoneParity/Notes
Basic CallingYes (IP phones, softphones, legacy SCCP/SIP support)Yes (Teams clients, SIP gateway for supported devices)Parity
Video CallingYes (native support)Yes (native support, but limited in interoperability mode)Parity, except Direct Routing (audio only)
Call TransferYes (attended, blind, early attended)Yes (attended, blind)Parity
Call ForwardingYes (Unconditional, Busy, No Answer)Yes (Unconditional, Busy, No Answer)Parity
Call Hold/ResumeYes (with Music on Hold)Yes (with Music on Hold)Parity
Three-way ConferencingYesYesParity
VoicemailYes (Unity Connection, MWI)Yes (Exchange/Teams Voicemail)Parity; centralized voicemail possible
Call ParkYesYesParity
Single Number ReachYes (ring desk phone & mobile/Teams)Yes (simultaneous ring, call forwarding)Parity
Auto AttendantYesYesParity
Hunt GroupsYesYesParity; some advanced features may need review
Call QueuesYesYesParity
Extension MobilityYes (login to any phone)Yes (hot desking, Teams devices)Parity
Device SupportBroad (IP phones, video endpoints, analog devices)Teams-certified devices, SIP Gateway for some Cisco phonesParity for most common use cases
Contact Center IntegrationYes (native & third-party)Yes (via certified solutions)Parity
Unified MessagingYesYesParity
MeetingsYes (Webex, video conferencing)Yes (Teams Meetings)Parity
File Sharing/CollabLimited (Webex integration)Yes (deep M365 integration)Teams stronger in collaboration
Security/EncryptionYesYesParity
Direct RoutingYes (via CUBE, PSTN, SIP trunks)Yes (Direct Routing, Operator Connect)Parity; video not supported in CUBE interop
Shared Line AppearanceYes (shared lines across devices)Limited/Not supported in interop modeCisco stronger
Callback/Call CompletionYesLimited/Not supported in interop modeCisco stronger


“We soon recognized that design and project planning is the critical place to get things right. The Cloud Revolution team did an exceptional job of not only helping us achieve a solid vision of where we should go, but also providing viable options along the way.”

  • Jake Jakel, IT Operations Manager at New Belgium Brewing.

Begin your Teams voice journey: Book a Microsoft Teams CloudDesign workshop

4. Selecting your PSTN connectivity

When you’ve planned what features need enabling and ensure Teams voice has all the settings and configurations you must retain, it’s time to think about PSTN connectivity.

Here, you have four options to choose from:

Options for Microsoft Teams voice PSTN connectivity

Operator Connect

  • Allows organizations to connect their existing telephony provider directly to Microsoft Teams.
  • Simplifies setup with no on-premises equipment required.
  • Managed through the Teams Admin Center for streamlined provisioning and management.
  • Offers carrier-grade reliability and support from certified telecom operators.

Direct Routing

  • Enables integration of Teams with a customer’s own Session Border Controller (SBC).
  • Offers maximum flexibility to use any telephony provider.
  • Ideal for complex or hybrid environments with custom routing needs.
  • Requires more technical setup and ongoing management compared to Operator Connect.

Microsoft Calling Plan

  • A Microsoft-managed telephony service that provides phone numbers and calling minutes.
  • Simplest option for organizations without existing telephony infrastructure.
  • Fully cloud-based and managed within Microsoft 365.
  • Available in select countries and regions.

Teams Phone Mobile

  • Extends Teams Phone capabilities to mobile networks via SIM-enabled devices.
  • Allows users to use a single number for both mobile and Teams calls.
  • Seamlessly switches between mobile and Teams networks based on availability.
  • Ideal for frontline workers and mobile-first users.

Each business will have its own unique requirements. Here, it’s best to consult a Teams consultant and/or MVP that specializes in Teams Phone if you’re not fully accustomed to the nuances of each Teams PSTN connectivity option.

Get clued up: Book your 2-day Modernize Communications Workshop.

5. Undertake Phone System enablement

With your choice of PSTN connectivity locked in, your next step is enabling those features that require such connectivity:

  • Number porting
  • Number activation
  • DID configuration
  • Shared line appearances
  • Call queues
  • Voicemail
  • Boss/Admin
  • Call Routing
  • Call forwarding
  • Calling and recording policies

You can set these up in the Teams Admin Center and test before you port your existing numbers to Teams voice.

Love the idea of Teams voice, but hate the sounds of ongoing management?

Check out how Revolution360 Managed Communications Suite can help you.

6. Integration and implementation planning

Hands-on work begins to implement the design. At this time, we build, configure, and test while working with you to plan how we will communicate changes to business users and provide the right level of training and user adoption support. We’ll review everything we’re going to test after go-live so you can sleep well after the cut-over to the new system.

Here’s what you’ll see during this phase:
  • Installing and configuring Teams Rooms Systems
  • Configuring auto attendants, call queues, and emergency services
  • User adoption planning, change management, and user acceptance
  • Contact center design and implementation (if applicable)

7. Roll out a Teams Phone pilot program

Before making the switch to Microsoft Teams for voice, it’s crucial to conduct a pilot program

to ensure the right fit and optimal outcomes. 

Cloud Revolution, the Microsoft partner of the year 2023 (and finalist 22, 24), offers a comprehensive solution to facilitate and manage your Teams Phone pilot.

We take care of everything for you:

  • Expert Facilitation: Our experienced team will guide you through the entire pilot program, ensuring best practices are followed and accurate results are obtained.
  • Goal-Oriented Approach: We work with you to define clear objectives aligned with your organization’s needs, providing a solid foundation for the pilot program and justifying its importance.
  • Leadership Buy-in: We help secure sponsorship from key stakeholders throughout your organization, fostering participation and diverse perspectives from different departments.
  • Resource Allocation: We assist in allocating the necessary time, resources, and budget for the pilot program, ensuring its success and seamless integration with your existing projects.
  • Defined Use Cases: We collaborate with you to identify and test the specific use cases relevant to your UC platform evaluation, ranging from conferencing and collaboration to mobility and third-party integrations.
  • Hardware Evaluation: As part of the pilot, we provide access to and gather feedback on hardware devices such as handsets, headsets, and conference room systems, ensuring comprehensive assessment and user familiarity.
  • Microsoft Support: Throughout the pilot, we leverage Microsoft’s dedicated resources, including training classes and technical documentation, to address any questions or unexpected situations that may arise.
  • Analysis and Implementation Planning: Our pilot program committee analyzes the outcomes, carefully considering any limitations or integration challenges.
  • Next Steps: Based on the findings, we collaborate with you to define the next steps for a successful full implementation plan.

Ready to start planning your Teams Phone pilot?

Book your free consultation with our Teams people.