A recent survey revealed that 62% of UK businesses are still using landlines within their company, and that 45% are unaware of an important and impending change that will eradicate them for good.
From December 2025, BT Openreach is closing down all ISDN lines – which will basically mean an end to landlines in the UK and the lines most commonly used to make phone calls across the world.
This means that any Public Switched Telephone Network (PSTN) - based products that your business uses today will need to change.
PSTN not only supports traditional landlines, but also voice services such as ISDN2/30. The bulk of widely available broadband services, such as fibre-to-the-cabinet (FTTC) or standard broadband (ADSL), also rely on the PSTN.
Voice will become completely digital and delivered over the internet using Voice-over Internet Protocol (VoIP) technology.
Broadband services will begin transitioning to Full Fibre (FTTP) and single order broadband (SOGEA). These don’t rely on landlines and are fully future-proofed, offering fast download speeds of up to 900Mbps.
Crucially, VoIP only requires an internet connection to work. This means you’ll be able to say goodbye to costly, old-fashioned analogue phone lines in all of your offices.
Known as ‘The Great Switch Off’, this is the biggest communications change in a generation.
It is happening because PSTN – which ISDN is a part of – has become outdated and been overtaken by these newer technologies, such as fibre broadband.
In September 2023, any broadband or phone services that use the old copper network will no longer be sold.
In December 2025, the PSTN will be switched off and all UK landlines will cease to operate.
From 1 January 2026 – all home or phone calls will be hosted via the internet.
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