For most organisations migrating from a traditional PBX to a VoIP phone system, the typical installation and setup timeline ranges from two to six weeks, depending on complexity, site readiness and the number of users. Simple, single-site deployments with good connectivity and minimal bespoke requirements can often be completed towards the shorter end of that range. Larger, multi-site or highly customised environments, especially where new connectivity, cabling or network upgrades are required, naturally take longer. The process usually follows clear stages: discovery and planning, network assessment and preparation, system configuration, installation, testing, training and final cutover. When each stage is properly managed, disruption can be kept to a minimum and the transition from PBX to VoIP can be completed with minimal downtime.
The initial planning and design phase typically takes one to two weeks and is crucial to an efficient rollout. During this time, current call flows, numbers, extensions and features are mapped, and a suitable VoIP solution is designed to match or improve upon existing PBX functionality. Network checks are carried out to confirm that broadband or leased lines can support voice traffic reliably. The physical installation and configuration stage usually takes a few days to a week, including setting up handsets, softphones, call routing, voicemail and any integrations with CRM or other business systems. After this, testing, user training and a controlled switchover are completed, often over a few days, to ensure staff are confident and the system is stable before the PBX is fully retired.
The first stage is assessment and planning, which commonly takes one to two weeks. During this period, current PBX usage is reviewed, including the number of users, call volumes, required features and any special routing or compliance needs. Network capacity and quality are checked, and a migration plan is agreed, including timescales, porting dates and any required infrastructure work.
The second stage is preparation and configuration, which typically takes another one to two weeks. This may involve upgrading connectivity, implementing quality of service (QoS), installing or checking structured cabling and configuring the VoIP platform. User accounts, extensions, call groups, auto-attendants and voicemail are set up, and test devices are deployed where appropriate.
The final stage is installation, testing and cutover, often completed within a few days. Handsets and softphones are rolled out, call flows are tested, users receive training, and numbers are ported. A brief parallel running period with the PBX may be used to ensure a smooth transition.
