The Quick Answer
For almost every UK business, VoIP is better than traditional phone systems. It's cheaper, more feature-rich, more flexible and — critically — the only option that works after January 2027 when BT permanently switches off all ISDN and PSTN lines.
Cost Comparison
The biggest difference between VoIP and traditional phone systems is cost. Here's a real-world comparison for a 10-person business:
Feature Comparison
Traditional ISDN systems were designed in the 1980s. VoIP was built for the modern business world:
Reliability: Which is More Reliable?
This is the most common concern when switching to VoIP. Traditional phone lines have a reputation for reliability because they work even when the power is out. VoIP needs internet connectivity.
In practice, for businesses with a decent broadband connection, VoIP reliability is excellent. Our Cloud X platform maintains 99.99% uptime. The key is having a failover arrangement — a 4G/5G backup connection that activates automatically if your main broadband drops. With failover in place, VoIP is more reliable in practice than traditional lines for most businesses.
What About SIP Trunks?
If you have an existing phone system (PBX hardware) that you're not ready to replace, SIP trunks are a middle ground. SIP trunks replace your ISDN lines while keeping your existing PBX hardware. You get the cost savings of VoIP without changing your phones or internal setup. It's the lowest-disruption route to PSTN compliance.
Should You Switch Now or Wait?
There's no good reason to wait. Businesses that switch now benefit from:
- Immediate monthly cost savings (typically 30–40% vs current ISDN bills)
- Access to features like call recording, mobile apps and AI reception immediately
- A planned, stress-free migration vs a forced switch in late 2026
- No risk of being caught out by early PSTN retirement in some areas
Frequently Asked Questions
Will VoIP work if my internet goes down?
With a failover connection in place, yes. We configure automatic 4G/5G failover on all Telexico VoIP installations — calls divert to mobile numbers within seconds if the main broadband drops. Without failover, VoIP calls would be unavailable during an outage, just as a traditional phone has no internet during a power cut.
Do I have to replace my phone handsets to switch to VoIP?
No. If you want to keep your existing PBX hardware, SIP trunks are the answer — they replace your ISDN lines while leaving your desk phones and system unchanged. Alternatively, Telexico provides new IP desk phones free with every full VoIP installation.
What is the PSTN switch-off?
BT and Openreach are permanently retiring the Public Switched Telephone Network (PSTN) and all ISDN lines by January 2027. After this date, all traditional analogue and ISDN phone lines will stop working. Every UK business needs a digital alternative — VoIP is the most common.
How long does it take to switch to VoIP?
Typically 5–10 working days from order to go-live. This includes number porting from your existing provider, hardware delivery and configuration. The switchover itself is usually done out of hours to minimise disruption.
Will call quality be as good as my current landline?
Yes — with a decent broadband connection, VoIP call quality matches or exceeds traditional landlines. HD voice (wideband audio) is standard on VoIP, giving noticeably clearer calls than analogue lines.
Switch Before the 2027 Deadline
Get a free quote today and we'll beat your current phone bill. Free handsets, free number port, no disruption.