Move enterprise voice to Teams Phone, starting with what you already own.
If your people live in Microsoft 365 but calls still run on Cisco, Avaya or a legacy PBX, voice is the last system outside Microsoft. ZIRO plans and runs the move, and the first step is knowing what your licensing already covers.
Six questions. Your result on screen. No email needed.
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Your phone system still works. The math around it may not.
Moving voice to Teams Phone is rarely about one feature. It usually starts with one of three things.
You may be paying twice
Microsoft 365 E5, E7, Office 365 E5 and A5 already include Teams Phone. If you also pay for Cisco or Avaya licensing, you’re funding two phone systems.
The University of New Haven had A5 licenses and was still paying $110,000+ a year for Cisco.
The hardware clock is running
Support dates turn working desk phones into upgrade bills. Most users on Teams Phone need a headset, not a new handset.
Replacing unsupported Cisco phones would have cost the university $250,000+.
The move is more than a license switch
Numbers, dial plans, carriers, sites and emergency calling all have to move without breaking. That’s the part that needs a plan.
BCF moved 600 people across two sites and kept its carrier.
A controlled move, not a big-bang cutover.
Old and new systems run side by side, so sites and teams move on your schedule.
- 01
Assess
Map your phone systems, sites, users, numbers, carriers and Microsoft licensing.
- 02
Design
Plan the Teams Phone setup, Direct Routing, and how both systems coexist.
- 03
Migrate
Port numbers, provision users and move sites in phases. Keep your carrier if you want to.
- 04
Manage
Run day-to-day changes in the ZIRO Platform, without PowerShell or the Teams admin center.
Start with what you already own.
Six questions. Rough numbers are fine.
- Whether your Microsoft licensing already includes Teams Phone
- How many users you’d likely license, in three scenarios
- Where spend and hardware may overlap
Your result shows on screen. No email needed.
Enterprises that made the move.
2,700+ employees on Cisco Call Manager, with A5 licenses that already included Teams Phone. ZIRO moved them in phases over six months, keeping emergency phones live the whole time.
“ZIRO didn’t just sell us a solution. They became an extension of our team. Their patience and responsiveness turned a chaotic transition into a manageable process.”
Greg Bartholomew, IT Director, University of New Haven
“It struck me how little negative feedback we got from the migration, and we can see people are using it every day.”
600 users, two sites, existing carrier kept
“ZIRO solved provisioning for me, and I can’t put a price tag on the time I’ve saved.”
Ekin Gümüş, Lead, Enterprise Voice Operations & Engineering
75 PSTN locations, provisioning automated
What IT leaders ask first.
Can we move from Cisco or Avaya in phases?
Yes. Old and new systems run side by side, so sites or teams move in a controlled order.
Do we have to change carriers?
No. With Direct Routing you can keep your current carrier and move to ZIRO’s service later if it makes sense. BCF did exactly that.
Does our Microsoft 365 plan include Teams Phone?
Microsoft 365 E5, E7, Office 365 E5 and A5 include Teams Phone Standard. E3, A3, F1, F3 and Business Premium don’t. The licensing check above shows where you stand.
What should we have ready before we start?
Rough user and site counts, your current phone system, your carriers, your Microsoft licensing, and any renewal or support dates coming up. Estimates are fine.
Six questions. Your number on screen.
See whether you already own Teams Phone before you plan anything else.
Check your licensingRather talk it through? Talk to a migration specialist
