BT Study Claims UK Digital Network Upgrades to Deliver £3bn in Economic Benefits

Broadband, mobile and telecoms giant BT has today published a new economic modelling study from Assembly Research, which examines how the ongoing migration from legacy networks (PSTN/WLR, 2G mobile etc.) to All-IP (Internet Protocol) services could “deliver billions in benefits” (£3bn) to the UK’s critical national infrastructure sectors.

At present BT (EE) and Openreach have a number of programmes that could be said to form part of this migration, such as their move from legacy to digital phone services, the withdrawal of 3G/2G mobile platforms, the closure of old telephone exchanges and the related migration of copper to full fibre (FTTP) broadband lines. But while in recent times much of the media’s attention has tended to focus on the disruption this causes, BT clearly wants to highlight the benefits too.

The new Assembly Research study broadly claims that a £3 billion net economic benefit could be realised across five key sectors by 2040, such as £1.4b in potential saving for the energy sector through improved resilience and demand forecasting. In the water sector, smarter network monitoring and reduced electricity usage could generate efficiencies worth £771 million.

The research evaluated the costs, risks and potential gains from digital migration across energy, water, health (NHS), emergency services and local government. It accounted for the direct cost of upgrading, as well as the rising expense of maintaining legacy systems like the Public Switched Telephone Network (PSTN) and the 2G mobile network – both decades old and increasingly challenging to support. Ofcom data shows resilience incidents on the PSTN have risen by 45%, underscoring the urgency of change.

Summary of Predicted Benefits by 2040

➤ Preventing 750,000 unnecessary ambulance trips – averaging more than 100 avoided journeys every day.

➤ Freeing up 12 million hours of council staff time – equal to around 6,500 staff working full-time for a year.

➤ Saving over 600,000 NHS staff hours – comparable to the annual workload of 350 full-time employees.

➤ Avoiding up to 280,000 false fire service callouts as businesses move away from legacy fire alarms – equivalent to 54 false alarms every day.

➤ Cutting 3.42 megatonnes of carbon emissions – equal to powering every home in Birmingham for a year.

Local governments, often under pressure to do more with less, also “stand to gain” £486m by modernising telecare systems and cutting the cost of maintaining ageing analogue equipment. In the NHS, digital transformation promises better call handling and more efficient emergency response. Meanwhile, emergency services could see fewer false alarms and improved call management, enabling faster, more targeted responses.

Jon James, CEO of BT Business, said:

“This research sends a clear message: delaying the shift to digital carries a real cost to public services, the environment and the wider economy. Legacy systems are becoming increasingly unreliable, and the case for action is urgent. BT is committed to guiding the UK’s critical national infrastructure sectors through this upgrade with the resilience and support they need.”

The UK’s transition to digital connectivity is a major national infrastructure programme endorsed by Ofcom and the Government. The Public Switched Telephone Network will be fully retired in January 2027 for the most vulnerable users, with businesses and public services urged to complete their migrations sooner – by the end of 2025 – to “avoid last-minute disruption“.

In 2024 alone, BT migrated nearly 300,000 legacy PSTN business lines. Yet the operator warns that “many CNI [critical infrastructure] providers in the UK still rely on ageing analogue systems for critical operations“, while other countries are moving faster (e.g. Germany and Spain are close to completing their migrations).

The report also claims that the “cost of inaction” could be £437m, although the report itself doesn’t make it easy to clarify how such a figure was produced. As usual, it’s often wise to take such economic modelling with a pinch of salt, not least because it’s incredibly difficult to verify and associate such impacts in the real-world.