The UK's copper phone network is being switched off for good on 31 January 2027. If your business is still running on old phone lines, this is the year it catches up with you, and the cost of waiting is already going up month by month.
This is a plain guide to what stops working, why delay gets expensive, and the order to do things in.
If you are searching for:
- PSTN switch off
- PSTN switch off date
- BT phone line switch off
- analogue phone line switch off
You are in the right place.
What is the PSTN switch off?
PSTN stands for Public Switched Telephone Network. It is the copper-wire system that has carried UK phone calls for well over a century.
Openreach is retiring it. From 31 January 2027, every analogue line and every ISDN line on that network stops working. Calls move to digital instead, running over an internet connection rather than a copper circuit.
Two quick points that often get muddled:
- ISDN sits on the same copper network, so it switches off on the same date
- This is not just a phone issue, which is where most of the nasty surprises come from
When is the PSTN being switched off?
The confirmed national date is 31 January 2027.
The key milestones:
- Stop sell since 5 September 2023 - no new analogue or ISDN lines
- Wholesale price rises through 2026 on legacy lines
- Full switch off on 31 January 2027
Openreach has made clear this date is firm and will not be delayed again.
Is the switch off actually happening, or will it be delayed?
It was delayed once, from December 2025 to January 2027, to give time to migrate vulnerable users safely.
That extra time is now nearly gone. As of June 2026, around 1.9 million lines were still to move, with several hundred thousand of those in business premises. Openreach's position is that there will be no further delay and no last-minute reprieve.
In short: if you are still on the old network, you are now late rather than early.
Why waiting is now the expensive option
The network has been frozen since the stop sell in September 2023. You can keep existing lines running, but you cannot order new analogue lines, do like-for-like swaps, or easily switch provider without upgrading.
On top of that, the cost of staying put is rising sharply. Openreach is increasing the wholesale price of legacy copper lines in three steps during 2026:
- around 20% from April
- a further 40% from July
- another 40% from October
That roughly doubles the annual cost of those lines by the autumn. Most providers pass this on, often in full and from the day it applies. So the line you are keeping "for now" gets more expensive every few months, while the migration you are deferring only gets more rushed.
What actually stops working?
The phones are the obvious part. The hidden dependencies are what catch businesses out. Check anything that might quietly dial out over a copper line:
- Lift emergency phones
- Intruder and fire alarm signalling
- Door entry and gate intercoms
- Older card payment terminals
- Fax and franking machines
- CCTV or monitoring kit that calls out
- Any analogue line feeding a forgotten service
A quick test: look for a line coming into a box on the wall rather than through your router. Anything not arriving via your internet connection is worth investigating.
Be careful with broadband too. If you are on an FTTC service, you may still rely on copper to reach the premises even though it feels modern.
What replaces the PSTN?
For voice, the answer is IP-based calling. Depending on your setup, that means:
Hosted VoIP / Cloud Phone Systems
A fully cloud-based phone system that replaces your old lines and hardware.
Microsoft Teams Phone
Common for businesses already on Microsoft 365, though not always a full replacement on its own.
SIP trunks
Keep your existing on-site system if it is compatible, and swap the lines underneath.
For the connection itself, the replacements are full fibre (FTTP) where available, or a fibre-to-the-cabinet service without a phone line where full fibre has not reached you yet.
Your existing numbers port across, so there is no need to change your number, reprint stationery or update your website.
What about power cuts?
Worth planning for. A copper line used to keep working on its own in an outage. A digital line needs local power.
For any phone that must stay up during a power cut, add a small battery backup (UPS) for your router. Providers are expected to offer at least one hour of access to emergency services, but a UPS keeps you covered locally.
Is there a safety net if I miss the deadline?
There is a fallback called EVAC (Emergency Voice Access). Be clear about what it is:
- emergency calls only
- it will not carry your broadband or any device signalling
- terms and availability are not expected to be confirmed until late 2026
- Openreach has signalled it may be restricted to critical infrastructure
EVAC is not a plan. It is what happens when you run out of time.
What should you do first?
You do not need to fix everything at once. You need to start in the right order:
- Audit your lines - find out what you have and what each line is actually used for
- Check your connectivity - confirm whether FTTP or FTTC is available at each site
- Plan the voice move - cloud system, Teams, or SIP on your existing kit
- Sort the non-voice devices - alarms, lifts, payment terminals, anything that dials out
- Port, test and cut over in batches - planned stages, not a risky overnight switch
The businesses that handle this well are not the most technical. They are the ones that started early enough to do it on their own terms, with options open and costs still low.
Still running on old phone lines?
If your business is still on PSTN or ISDN, now is the time to review your options.
At West Pier Technologies, we help UK organisations move off the old network onto modern solutions including VoIP, SIP, Microsoft Teams telephony and full unified communications platforms.
We will:
- audit your current lines and flag hidden dependencies
- confirm the right connectivity for each site
- keep your existing numbers
- manage the migration with no gap in service
Contact West Pier Technologies today to plan your switch off the PSTN.
