· Luke Faragher · Industry · 6 min read
Why Is BT Switching Off Landlines? The Real Reason.
The official story is modernisation. The fuller picture involves £6 billion in copper, rising exchange costs, and a commercial case that rarely gets mentioned in the communications you receive from BT.
The deadline is 31 January 2027. After that, traditional copper landlines stop working across the UK. Around 14 million homes and businesses are affected.
BT’s messaging on this has been consistent: copper is old, fibre is better, the future is digital. None of that is false. But I’ve been in this industry since 2013 and there’s a lot that doesn’t get said in those consumer communications. This is my attempt to say it.
There’s £6 billion sitting in the ground
Openreach’s copper network isn’t just a piece of legacy infrastructure to be retired. It’s a physical asset worth several billion pounds in scrap value, and recovering it requires switching the network off first.
Openreach has publicly confirmed it expects to extract up to 200,000 tonnes of copper from the network through the 2030s. In the year to March 2024 alone, it pulled out 3,300 tonnes and received £105 million for it from recycling partner EMR. That’s roughly £31,800 per tonne. Multiply that across 200,000 tonnes and you’re looking at figures in the region of £6 billion.
| Metric | Figure |
|---|---|
| Copper recovered (year to March 2024) | 3,300 tonnes |
| Revenue from recycling (same period) | £105 million |
| Value per tonne (approx.) | ~£31,800 |
| Total copper projected for recovery | 200,000 tonnes |
| Indicative total value at current rates | ~£6 billion+ |
This isn’t a secret. Openreach discloses the extraction programme in investor materials. There’s a deal in place with EMR running until 2028 specifically to manage it. What you won’t find is any of this in the letters BT sends customers explaining why their landline is going away.
Exchanges cost a fortune to run
On top of the copper itself, BT operates thousands of local telephone exchanges across the UK. These are buildings full of circuit-switching equipment that exists purely to route traditional PSTN calls. Power, cooling, maintenance, business rates, staffing costs — all of it running continuously, for a declining volume of calls on ageing kit.
Once customers move to all-IP services, those buildings become redundant. BT can close them, sell the sites, and eliminate the ongoing running costs permanently. That’s a significant commercial benefit that has nothing to do with broadband speeds.
I’m not saying the switch-off is wrong. The decisions are rational. But “modernisation” as the sole explanation papers over a straightforward asset recovery and cost reduction programme that’s been in the works for years.
It’s the same story as 3G
If this feels familiar, it should. When EE switched off 3G in 2024, the public narrative was built around environmental improvements and better 5G coverage. What got far less coverage: 3G was consuming around 35% of EE’s total mobile network electricity while carrying just 0.6% of all data traffic and 7% of voice calls. Even being generous on the voice side, that’s an extraordinary amount of power for the traffic it was shifting.
But here’s what that 7% voice figure actually means. EE knew that switching 3G off would make voice calls materially worse for a meaningful chunk of customers, particularly indoors. 3G’s lower frequencies penetrated buildings, basements, and thick-walled properties far better than 4G does at higher frequencies. They switched it off anyway, because the electricity bill saving outweighed the customer impact.
In-building coverage has got noticeably worse since the 3G switch-off as a direct result. That signal getting into your basement or your Victorian office is largely gone. And with some operators now talking about switching off 2G, the last reliable fallback for voice in weak signal areas goes with it. The customers who bear that cost aren’t mentioned in any press release.
Same pattern as PSTN, different infrastructure. The narrative leads with the benefits. The costs to customers get a paragraph at best.
What actually happens to your business
The January 2027 deadline isn’t moving again. Openreach already pushed it back once from December 2025. Since early 2026, they’ve been hiking PSTN line rental prices to force faster migration. The message is clear enough.
A few things small businesses often miss:
Phone lines. Any copper landline, whether BT, Sky, or TalkTalk, stops working. That includes lines running DECT handsets, fax machines, and alarm diallers.
Card terminals. Older EPOS equipment that dials out over PSTN will fail. Most modern terminals already use 4G or broadband, but it’s worth checking older kit, especially in retail and hospitality.
Alarm systems. Intruder alarms, fire alarms, and personal care alarms with a PSTN dialler are probably the most overlooked risk. If someone in your family relies on a personal alarm service, this needs checking now, not in December 2026.
What to do about it
We’ve been running mobile-network-based landline services at ONSIM since 2013, before the switch-off was announced and before any of this became a mainstream conversation. None of our products touch copper. Here’s what we offer, depending on your situation:
Virtual Landline from £5/month — the simplest option. Your existing 01, 02, or 03 number forwards to your mobile. No new hardware, no SIM swap, no app. If you just need your business calls to keep reaching you after January 2027, this is where to start. You can keep your existing number throughout.
Landline SIM from £10/month — for those who want to do more than just receive calls. Your landline number lives natively on a SIM in your mobile, so you can also make outbound calls that show your landline number. Same mobile network reliability, but with full two-way calling from your handset.
Landline Replacement — launching soon — for anyone who wants to keep their existing desk phone or analogue handset exactly as it is. We ship you a small box (a SIM ATA), you unplug from the BT socket and plug into the box instead, and your phone works as normal over the mobile network. No broadband required, works with alarms and analogue phones, and your number comes with you. We’re taking names on the waitlist now.
All three work during power cuts at the phone end, none require broadband, and all can carry your existing number across.
BT’s switch-off is happening on BT’s timetable, driven by BT’s economics. Your job is just to have something sorted before the lights go out.
Luke Faragher is the founder of ONSIM, which has provided SIM-native virtual landlines to UK businesses since 2013. ONSIM is an independent mobile network and is not affiliated with BT Group or Openreach.
