What Is the PSTN and Why Is It Being Switched Off?
The Public Switched Telephone Network (PSTN) is the UK’s traditional copper wire telephone infrastructure, the network that has delivered landline calls for decades. BT Openreach has announced it will be shut down by 31 January 2027.
The reason is straightforward: the copper network is ageing, expensive to maintain, and increasingly unreliable. Digital alternatives, including Voice over Internet Protocol (VoIP) and IP telephony, offer better reliability, greater scalability, and lower running costs. As the majority of businesses and consumers have already moved to digital communications, maintaining the old copper infrastructure makes less and less sense.
What This Means for Most Businesses
For most businesses, the practical impact will be minimal. If your phone system already runs over the internet via VoIP, or if you use a cloud-based phone platform, you are already on digital infrastructure and the PSTN switch-off will not affect your day-to-day communications.
Business internet connections that run over fibre, leased lines, or FTTC are also unaffected. The switch-off specifically relates to the old copper analogue telephone lines.
Hidden Legacy Technology to Check
The risk for businesses is not usually their main phone system. It is the equipment that quietly runs in the background on a PSTN line that nobody has reviewed for years. Before the January 2027 deadline, it is worth checking the following:
Door entry systems and car park barriers
Older access control systems may use a PSTN line for remote operation or alerts. Check with your supplier whether the system needs upgrading or can be migrated to a digital connection.
Fax machines and analogue phones
If your business still uses fax machines or analogue desk phones connected to a copper line, these will stop working after the switch-off. VoIP alternatives are available for both.
Lift alarm systems
Lift emergency alarm systems frequently use PSTN lines. This is a safety-critical system, so confirming compatibility and arranging migration well before the deadline is important.
PDQ machines and cash terminals
Older payment terminals may connect over PSTN. Speak to your card payment provider to confirm whether your terminals will be affected and what migration path is available.
Panic alarms and care systems
Personal and building alarm systems, including BT Redcare-connected systems, may depend on PSTN. These should be assessed and migrated to digital alternatives before the switch-off date.
Support Across the North West
Blowfish Technology can review your communications infrastructure and help identify any systems still dependent on PSTN. We provide VoIP and hosted telephony solutions for businesses across Lancashire and the wider North West, including IT Support Skelmersdale, IT Support Preston, and IT Support Southport.
The Blowfish Technology team. Managed IT, cloud services, software development and connectivity for North West businesses since 1999.