Replacing a Phone System With the Software Everyone Already Had Open

The challenge

Calling ran through a traditional provider with its own infrastructure to maintain and its own invoice, for an organisation whose staff already spent the day in Microsoft Teams. Departmental lines needed to reach the right group of people, and reception needed shared devices — neither of which the existing setup made easy to change.

Where we came in

Phone migrations are mostly a routing design problem wearing a telephony costume. We ran a discovery session and drew the call flow visually before configuring anything, because the expensive mistakes are made in the routing logic, not the licensing — and emergency calling has to be configured deliberately, not assumed.

What we did

• Ran a call routing discovery session and designed the call flow visually before building
• Configured an auto-attendant with greetings, and call queues for departmental routing
• Ported the existing numbers rather than issuing new ones
• Configured shared device handling for common-area phones
• Configured emergency calling explicitly as part of the deployment
• Applied Teams Phone policies so the configuration is governed rather than per-user

Where it landed

• Calling runs inside the collaboration platform staff already use, with the separate provider retired
• Departmental calls route through queues to a group rather than to one person's handset
• Emergency calling and shared devices were configured as part of the build