The switch-off won't be a 'big bang' — but the deadline still stands
Openreach says there won't be a single overnight cut-off in 2027, and the number of old lines is falling fast. The businesses left on legacy lines are the ones paying for it.
The old phone network is being switched off by 31 January 2027, and that date is not moving again. What's changed in the past few weeks is the tone from Openreach: there won't be a single overnight cut-off. Lines will be moved across in stages, and anyone still on the old network after the deadline gets handled case by case rather than simply disconnected. That sounds reassuring. For most businesses it isn't a reason to wait.
The numbers are dropping fast
About 1.9 million UK lines are still on the old Wholesale Line Rental network, down from roughly 2.5 million in April 2026. Several hundred thousand of those serve business premises. The migration is clearly speeding up as the deadline gets closer, and some providers are already on track to clear their remaining lines to zero before January. The pool of businesses still to move is shrinking, which means the available engineering and support time gets tighter, not looser, as 2027 approaches.
'No big bang' is not the same as 'no rush'
Openreach has said there won't be a big bang on 1 February 2027. After the deadline, remaining lines are assessed and some are moved onto a basic emergency voice service as a stopgap. That service is a last resort: it carries phone calls only, so any broadband running over the same line stops. For a business, that is not a position you want to land in by accident. The phased approach is about avoiding mass disconnection chaos, not about handing anyone extra time to plan.
ISDN business lines have nowhere to go
If your phones run on ISDN2 or ISDN30, there is no like-for-like replacement waiting. Those services cease at the switch-off, and the route forward is internet-based calling. The same applies to anything else quietly sharing a phone line: alarms, lifts, door entry, card machines. Each needs checking and, where needed, moving to an internet-based equivalent before the line goes.
Staying on old lines now costs more
Openreach has doubled the price of legacy copper line products through 2026 to push migration along, and it has worked. Where keeping an old line once felt like the cheap do-nothing option, it now means paying a rising amount for a service with a fixed end date. Moving to a cloud phone system over your internet connection usually lands at a lower, more predictable monthly cost, and you keep your numbers.
What this means for your business
If your phones, or anything running over a phone line, still sit on the old network, the calm version of this move happens now, not in a 2027 scramble. We'll audit what you've got, tell you plainly what moves easily and what needs a different plan, keep your numbers, and switch you over with no gap in your phones.
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Ready when you are.
Tell us what's slowing your business down. We'll tell you exactly how we'd fix it — plainly, with no obligation.