The UK's copper phone network is being switched off. If your business still relies on PSTN lines, ISDN circuits or landline-dependent broadband, this page is your starting point for what replaces them, and how to move without disruption.
PSTN replacement means moving any service still running on the UK's analogue phone network - voice lines, ISDN circuits, alarm signalling, older broadband - onto a digital alternative such as SIP trunking, hosted voice, FTTP or SoGEA, ahead of the full network switch-off on 31 January 2027.
We've covered the switch-off deadline and timeline in detail elsewhere on this site - see our full PSTN switch-off guide for exchange-by-exchange dates. This page is about the decision that actually matters once you know the deadline: which digital alternative replaces which service, and how to get there.
Openreach is retiring the PSTN and ISDN networks. New copper orders have already stopped across most of the UK, exchanges are migrating area by area, and the whole network closes on 31 January 2027. Once your local exchange has migrated, anything still running on copper - phones, ADSL broadband, alarm lines - simply stops working, with no grace period. Read the full timeline here.
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What's actually affected
It's not just phone lines. Anything that quietly relies on an analogue connection is exposed:
Voice & phone systems
PSTN analogue lines
ISDN2 and ISDN30 circuits
Fax machines
PDQ / card payment terminals
Broadband & connectivity
ADSL and FTTC circuits
Older routers built around a phone line
Single-site internet with no backup path
Critical & safety systems
Fire and intruder alarm signalling
Door entry and intercom systems
Lift emergency phones
Out-of-hours and telecare devices
Have you checked all of these?
Tick off anything your business still has running. Most businesses find at least one item here they'd forgotten was still on copper.
None of this fails gracefully. When your local exchange migrates, unmigrated services don't get a warning, they simply stop. For phone lines that means lost calls. For alarm signalling and lift lines, it can mean a safety-critical system going silent without anyone noticing until it's tested. Planning the move now, rather than reacting to an outage, is the difference between a managed project and an emergency call-out.
How we help
Audit
We map every PSTN and ISDN-dependent line and service across your business, including the ones nobody remembers are still on copper.
Design
We match each service to the right replacement - SIP trunking, FTTP, SoGEA, hosted voice, or resilient 4G/5G backup - based on what you actually need, not a one-size-fits-all switch.
Pilot
We test the replacement on a small site or line group first, checking call quality, failover and number routing before wider rollout.
Rollout and numbering
We coordinate the wider migration, port your existing numbers, and schedule changes to avoid disruption to calls or connectivity.
Ongoing support
Once you're migrated, we monitor and support the new setup as part of your existing Wavenet service.
Your replacement options
Voice & phone systems
Hosted UCaaS- cloud-based phone system, no on-site hardware to maintain
Phone systems- handsets and infrastructure, fixed-line or cloud-based
SIP Trunking- keep your existing PBX, replace the line it runs on
Fire and intruder alarms, lift emergency phones, door entry systems and other connected devices often rely on the same copper lines as your phones, and they're just as exposed. The principle is the same as the rest of this page: replace the analogue line with a resilient digital connection, typically 4G or 5G backup sitting behind your existing signalling equipment. If you're not sure which of your critical systems are still running on copper, that's exactly what the audit step above is for - talk to us and we'll help you work out what needs attention and in what order.
What breaks first depends on what your sector runs over a phone line. A few examples of what we typically see:
Healthcare
Telecare and nurse call alarms, patient monitoring devices and out-of-hours GP lines often still run on analogue circuits, alongside referral processes that still rely on fax.
PDQ card payment terminals, EPOS systems and store alarm signalling are commonly tied to a phone line, especially across multi-site estates with older infrastructure.
Lift emergency phones, door entry and intercom systems, and fire and intruder alarm signalling across managed sites are among the most exposed - and most safety-critical - copper dependencies.
Fire alarm signalling to monitoring stations, site intercoms and reception phone lines across school and campus buildings frequently rely on the same ageing analogue infrastructure.
Finance
Compliance-critical call recording, vault and physical security alarm signalling, and card payment lines all depend on connections that need a planned, tested replacement.
Manufacturing
Site-wide safety comms, emergency help points on the factory floor, and older equipment using analogue modems for remote telemetry are easy to overlook until they stop working.
Construction
Temporary site offices, portable cabin phone lines and site security monitoring are typically set up and torn down project by project, making them easy to miss in a single company-wide audit.
Depot alarm, barrier and gate access systems, PDQ terminals, and cold-chain telemetry lines often run on analogue circuits across dozens of sites, many unstaffed and operating through the night when a fault is least likely to be noticed.
It's the process of moving any service that currently runs over the UK's analogue phone network (PSTN or ISDN) onto a digital alternative - SIP trunking, hosted voice, FTTP, SoGEA, or 4G/5G connectivity - before the copper network is switched off.
When do we need to have moved by?
The final UK-wide switch-off deadline is 31 January 2027, but many exchanges migrate earlier than that. Once your local exchange has moved, anything still on copper stops working immediately, so the practical deadline for your business is often sooner than the national one. See our full switch-off timeline for exchange-level detail.
Can we keep our existing phone numbers?
Yes. Number porting is a standard part of migrating to SIP trunking, hosted voice, or Direct Routing for Microsoft Teams, so your business keeps the same numbers your customers already call.
Do we have to move everything at once?
No. Most businesses migrate in phases, starting with the highest-risk or highest-value lines first. A phased rollout with a pilot group is usually less disruptive than moving everything at once.
What if we're not sure what's still running on copper?
That's the most common starting point. An audit is the first step of the process above, and it typically turns up more copper-dependent devices than businesses expect - alarm panels and lift lines especially.