Phase 1: Decide What You Are Replacing and What You Are Keeping
The first decision is scope. Are you replacing just the phone system? Or are you also consolidating video conferencing, team messaging, and fax into the same platform? The scope determines which provider capabilities you need to evaluate and how complex the migration will be.
Most businesses that are migrating from a legacy PBX benefit from consolidating all communications into a single UCaaS platform at the same time. Doing it in phases sounds safer but often extends the parallel-operation period unnecessarily and creates integration headaches.
Phase 2: Assess Your Network Readiness
Cloud communications depend on your internet connection. Before selecting a provider, assess the quality of your internet at each location where the system will be deployed:
- Minimum bandwidth: 100 kbps per concurrent call, plus headroom for other traffic
- Latency: Under 150ms round-trip to the cloud provider's nearest data center
- Packet loss: Under 1% for acceptable call quality
- Jitter: Under 30ms for consistent audio quality
If your current internet connection does not meet these thresholds, address the network before or alongside the phone system migration, not after. Network quality issues after go-live are the most common cause of migration regret.
Phase 3: Select a Provider and Get Your Contracts Right
Provider selection should be based on feature fit, migration support quality, and total cost. Once you select a provider, pay attention to the contract details:
- What is the contract term? Month-to-month versus annual affects flexibility.
- What support SLA is included in your plan tier?
- Is number porting included or does it carry additional fees?
- What happens to service if you exceed your contracted users?
Phase 4: Execute the Number Port
Submit your number port request as soon as your contract is signed. Provide complete and accurate information on the first submission. Port requests rejected for errors restart the timeline. For a business with more than 20 numbers, consider using your provider's porting team rather than doing it yourself.
Phase 5: Configure, Train, and Cut Over
While the port is in process, configure your new cloud system completely. Set up every user, auto-attendant, call group, and routing rule. Run a full test of all call flows with a pilot group before the cutover date. Schedule the cutover for a low-traffic period, have your provider on standby, and confirm a rollback plan exists if something goes wrong on the first day.
Post-Migration
After cutover, monitor call quality for the first two weeks more carefully than usual. Address any routing issues quickly. Gather feedback from staff on the new system and address adoption issues before they become habits. Keep the old system accessible (but offline) for at least two weeks as an emergency fallback.
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