Number porting lets a customer keep an eligible telephone number when changing provider. The gaining provider submits the request using matching account and number details. Do not cancel the existing service before the port is accepted, and check whether broadband, alarms, payment terminals or other services depend on the old line.
What number porting does
Number portability is the regulated facility that allows customers to retain eligible numbers when changing communications provider. The gaining provider coordinates the request, while the losing provider validates the number and account information.
A port moves the number's routing. It does not automatically move handsets, broadband, voicemail, call recordings, contact-centre settings or PBX configuration.
Information normally required
Port requests fail most often when the submitted details do not match the losing provider's records. Gather the latest bill or account record before starting and identify every number that belongs to the service.
Complex ranges can contain a main billing number, individual DDIs and numbers that are not actively advertised. Porting only part of a range can have consequences, so ask the providers to confirm the full range and any associated services.
- Customer or legal business name held by the provider.
- Current provider and account number.
- Installation or service address.
- Main billing number and every number to be ported.
- Whether the numbers form a single line, multi-line service or DDI range.
- Authorised contact details and requested migration date.
Check services attached to the old line
A traditional line may support more than voice. Broadband, fax, alarms, lift lines, door entry, payment terminals and monitoring equipment can be affected if the underlying service is ceased.
Document each dependency before the port. Some equipment should move to a separate modern connection or specialist service rather than being assumed to work over VoIP.
Build and test the new service first
Configure the new SIP trunk, hosted phone system or call-divert route before the established number moves. Use temporary numbers to test inbound calls, outbound caller ID, queues, opening hours, voicemail and failure routing.
On the migration date, test calls from more than one network and confirm all DDIs. Keep an escalation contact available at both providers.
- Do not cancel the losing service before acceptance.
- Agree the port date and expected interruption window.
- Test inbound, outbound and transferred calls.
- Confirm emergency-calling information where relevant.
- Keep a fallback number available for customer communications.
What happens if a port is rejected?
A rejection does not necessarily mean the number cannot be ported. It often means that a name, address, account reference, number range or service type does not match.
Ask for the specific rejection reason, correct the evidence and resubmit. Avoid repeated speculative submissions because they can delay the migration and make the audit trail harder to follow.
UK business number-porting support
Submit a UK number-porting enquiry and plan delivery to SIP, hosted VoIP or call divert.
Start a porting enquiry