The Old Line Is Going: What UK SMEs Need to Check Before PSTN Retires

Let's start with the good news: the retirement of the UK's old telephone network is not a surprise. It has been signposted for years. The less good news is that the thing most SMEs forget is not the phone on the desk. It is everything else that quietly depends on a traditional phone line.

If your business still has a PSTN or ISDN line, you are not alone. Plenty of small firms are in the same boat. The goal here is not to panic-buy a shiny new system. It is to check what you have, understand what needs to move, and do it in a sensible order.

What is actually changing?

The Public Switched Telephone Network — PSTN — is the old copper network that has carried voice calls for decades. ISDN is the business-grade cousin. Both are being retired as the UK moves to internet-based voice services. Openreach has already stopped selling new traditional lines in many areas, and providers are moving customers onto digital services.

The final dates have shifted before, and they may shift again. But the direction of travel is clear. The risk for an SME is not usually the desk phone. It is the alarm, the lift line, the payment terminal or the fax machine that nobody has thought about since it was installed.

The obvious stuff — and the not-so-obvious stuff

Start with a walk around the building. Anything with a phone socket is a candidate. That includes:

• desk phones and cordless handsets
• fax machines (yes, they are still out there)
• card payment terminals and EPOS tills
• intruder alarms and fire alarm signalling
• lift emergency lines and access phones
• door entry systems and CCTV diallers
• out-of-hours monitoring or nurse call systems
• analogue modems, data loggers and legacy kit

The sneaky ones are the devices that use a phone line but do not look like phones. A lift line might be wired into a small box in a cupboard. An alarm might use a redialler. A payment terminal might have a phone lead as well as a power lead. If it has a phone socket, a battery backup or a contract with a monitoring centre, put it on the list.

A calm, step-by-step checklist

1. Find every line and socket. Ask your provider for a list of active lines and services. Check the bill, then check the cupboards. The bill is not always the whole story.
2. Write down what is connected. Make a simple table: location, device, who owns it, who maintains it. Take photos of the sockets and labels. Future you will be grateful.
3. Call your provider and ask the awkward questions. Which services are moving? Which are not supported? What happens to your number? What notice do you need to give?
4. Check the specialist systems first. Alarms, lifts, payment terminals and monitored systems often need a specific digital solution. Ask the maintainer, not just the telecoms provider. Get it in writing.
5. Decide how you want to make calls. A hosted VoIP system is the usual route for SMEs. But you do not need to buy every feature on day one. Start with what you use.
6. Plan number porting early. You want to keep your main business number. Porting is usually straightforward, but it needs coordination. Do not leave it to the week of the switch.
7. Sort out power and connectivity. Digital phones need power and internet. A basic UPS on the router and key handsets is cheap insurance. Check what happens if the broadband drops.
8. Test before you rely on it. Call internally, call externally, test voicemail, test the alarm, test the payment terminal. Run a quiet pilot if you can.
9. Tell staff and customers. A short note on the new way to call, transfer and check voicemail prevents a lot of grumbling.
10. Keep a record. Contract dates, support contacts, what was migrated and what was not. It makes the next renewal much easier.

The traps that cost money

There are a few easy ways to overspend. Buying new handsets for every desk when half the team mostly uses headsets. Signing a long contract before you know what the alarm needs. Paying for a maintenance contract on a system you are about to retire. Or assuming a cheap adapter will solve a lift line when it will not.

The sensible approach is to migrate what needs migrating, keep what still works, and avoid buying a Ferrari when you need a reliable estate car. At Eden Telecoms, we have seen more SMEs overspend by rushing than by waiting a week to check the alarm.

How long should it take?

For a simple office with a few phones, a few weeks is usually enough. If you have alarms, lifts, payment terminals or multiple sites, give yourself two to three months. The businesses that struggle are the ones that start late and discover a connected system nobody knew about.

The bottom line

You do not need to be an engineer to get this right. You need a list, a few phone calls and a bit of patience. Check the obvious, check the hidden, and get the specialist systems signed off by the people who maintain them. The old line is going. A calm plan is cheaper than a panic.