About Us

Transition Advisory Service is a UK-based consultancy specialising in helping businesses prepare for the nationwide ISDN/PSTN switch-off. We provide independent advice, clear guidance and cost-effective upgrade solutions tailored to your organisation.

Our mission is to ensure every UK business transitions smoothly with minimal disruption.

Why Transition Advisory Service?

  • Independent and provider-neutral

  • Specialists in ISDN/PSTN switch-off compliance

  • UK-wide support

  • Fast, friendly and clear communication

  • Solutions for businesses of all sizes

  • Transparent pricing and straightforward advice

Frequently Asked Questions

If your specific query is not addressed here, please contact us for a direct conversation.

Your phones, alarms, lift lines and other services may stop functioning.

Not always — but every business must move away from analogue lines.

ADSL and FTTC rely on ISDN/PSTN. You may need fibre or SOGEA.

Yes, we can coordinate with your existing supplier or recommend alternatives.

Book Your Free Consultation

Get expert advice on how the ISDN/PSTN switch-off will affect your organisation and your best upgrade options.