Business Phone-System Migration Checklist

Plan the move around your business

A phone-system migration affects more than the equipment on your desks. Customers need to reach the right team, staff need to know how to answer and transfer calls, and any services connected to the old lines need checking.

This checklist works as a starting point whether you are moving from a traditional system to hosted VoIP or replacing an existing VoIP provider. Assign an owner to each task and record what still needs supplier confirmation.

For businesses still using traditional lines, Openreach currently identifies 31 January 2027 as the move-to-digital deadline. Check your own services with your provider and begin planning early. This does not mean every existing VoIP customer needs to change supplier.

Before choosing a replacement

• Name one person to coordinate the project and supplier communications.
• List the current phone services, sites, users and contracts.
• Record every number that needs to be retained.
• Check termination costs and separate equipment agreements.
• Describe the problems the replacement needs to solve.
• Record required functions, such as transfers, shared ringing, voicemail and out-of-hours routing.
• Compare total costs, including setup, equipment, calls and support.

Define success in practical terms. For example, reception may need to transfer calls reliably, while staff away from the office may need an approved way to answer the business number. Agree these requirements before choosing a package.

Check connectivity and connected equipment

• Ask the supplier to assess connection quality and expected simultaneous calls.
• Check router, network-switch, cabling and handset requirements.
• Identify power supplies or Power over Ethernet requirements.
• List alarms, payment terminals, entry systems and other devices using existing lines.
• Ask each equipment supplier to confirm digital compatibility and any changes needed.
• Agree what should happen during an internet or power outage.
• Test the proposed backup arrangement and understand its limitations.

Digital calling depends on connectivity and powered equipment. A battery for one device does not necessarily keep the whole calling path available. Ask the supplier to explain the proposed resilience arrangements for your setup.

Prepare numbers and call routing

• Obtain confirmation that the receiving provider can accept the required numbers.
• Supply the requested account details and transfer authorisation.
• Check for dependencies between phone numbers and other services.
• Agree the transfer date or window and an escalation contact.
• Prepare opening-hours, holiday and voicemail messages.
• Map which phones or users should ring for each incoming number.
• Agree caller-ID settings and ask how emergency-service location information should be maintained, especially for remote users.

Use our number-transfer guide for more detail. Keep existing services active until the transfer is complete and the relevant provider confirms the next steps.

Get staff ready

• Set up approved phones, apps and headsets.
• Secure administrator accounts and use multi-factor authentication where available.
• Give staff only the access they need.
• Practise answering, transferring and retrieving voicemail.
• Provide a short help sheet and support contact.
• Confirm recording settings and internal approval if call recording is required.

A brief practice session can reveal misunderstandings before customers encounter them. Include the people who answer calls most often, rather than leaving testing entirely to the project organiser.

On the day of the move

• Have a site contact available and confirm the supplier's support arrangements.
• Wait for confirmation of the number transfer.
• Test incoming calls to each important number from an external phone.
• Test outbound calls and displayed caller ID.
• Check transfers, voicemail, ring groups and opening-hours rules.
• Test apps and handsets used away from the main office.
• Log faults and assign an owner to follow them through.

Do not place test calls to emergency services unless an authorised test has been arranged through the appropriate process. Ask your supplier how to verify emergency-calling configuration safely.

After go-live

• Ask staff about missed calls, audio problems and confusing controls.
• Review routing against real working patterns.
• Reconcile final charges and confirm which old services can be closed.
• Keep configuration records and support details accessible.
• Schedule a follow-up review after the team has used the system.

Discuss your migration with Alliance Consultants

Tell us what you have now, how many people use it and when you would like to move. We can discuss a suitable next step based on your requirements.

Call 01256 807707 or email hello@allianceconsultants.co.uk.

See also UK small-business VoIP costs explained.

Further reading: Openreach: switching your business to digital.