ISDN Replacement UK
ISDN replacement: switch ISDN2 and ISDN30 to the cloud
ISDN lines are being retired in 2027. Replace your ISDN2 and ISDN30 circuits with a UK cloud business phone system, keep every number and cut your line rental.
Get a QuoteWhat is ISDN?
Integrated Services Digital Network is the digital phone line service many UK businesses have used for years, in ISDN2 (2 channels) and ISDN30 (up to 30) variants.
Why is it ending?
ISDN is being retired alongside the PSTN. New ISDN circuits are no longer sold and the technology is being switched off.
ISDN switch off
When is the ISDN switch off?
ISDN2 and ISDN30 are being withdrawn nationwide alongside the PSTN, with the final switch off due in 2027.
New ISDN circuits are no longer sold, and existing ones are being switched off area by area as exchanges are upgraded. If your business still runs calls over ISDN, you will need a replacement before your exchange date rather than after it — porting numbers takes days, not minutes, and the last few months before a deadline are always the busiest for engineers.
You can check the current timetable in our guide to the ISDN switch off date, the ISDN switch off deadline and timeline, or read the wider PSTN replacement guide.
Leeds and Yorkshire
ISDN switch off support in Leeds
We are based in Leeds and handle ISDN2 and ISDN30 migrations across Yorkshire.
Leeds businesses with an older on-site PBX are among the most affected: manufacturers on the industrial estates, professional firms in the city centre and multi-site operators across LS postcodes all tend to have ISDN30 sitting behind their main number. We survey what the system does today, port every 0113 number, and either replace the PBX with a cloud phone system or keep it running on SIP trunks.
Call 0113 522 0000 to talk it through with the Leeds team, or see Leeds business phone systems for local pricing and timescales.
Cloud Alternatives
Modern replacements for ISDN
Hosted Phone System
A full cloud phone system for your whole team.
SIP Trunks
Keep your existing PBX, replace the underlying ISDN circuits.
Hybrid
Mix desk phones and apps with central call routing.
FAQ
Frequently asked questions
Ready to switch to a smarter phone system?
Special offer: free number port and free setup — worth £174. Talk to a UK specialist today, no pressure and no jargon.