As the UK prepares for the complete decommissioning of the Public Switched Telephone Network (PSTN) by 2027, the implications for national infrastructure and essential services are coming into sharp focus. With over 300 identified use cases relying on this long-established copper-based network, the transition presents significant logistical, operational, and technical challenges across multiple sectors.
This analog-to-digital shift will fundamentally change how critical national systems operate, communicate, and ensure continuity—especially in remote and high-dependency environments.
National Infrastructure: The Hidden Dependencies
The UK’s national infrastructure has been intertwined with PSTN connectivity for decades, resulting in deep-rooted dependencies that are often only visible when attempting to replace them. PSTN connections form a silent backbone for systems related to monitoring, control, and emergency response across essential public and private sector operations.
Many of these connections are not just used for voice calls—they underpin a wide range of machine-to-machine (M2M) communication and low-data-rate telemetry applications. These are typically used in monitoring and alert systems that require always-on, ultra-reliable connections with very low power draw.
The scale of the challenge is immense. From healthcare to utilities, transportation to housing, and energy to emergency services—PSTN is embedded in thousands of critical systems that must now be migrated to resilient, digital alternatives.
Several areas are facing potentially significant cost increases, including:
- Telecare services for vulnerable populations
- Traffic management systems and roadside assets
- Housing association-managed monitoring infrastructure
- Local government services in remote or rural locations
These cost increases stem not only from equipment upgrades, but from the need to install digital connectivity, ensure power resilience, and meet stringent uptime requirements.
Energy Distribution Networks
The National Grid and regional energy distribution networks operate vast systems of remote substations and telemetry sites, many of which have historically relied on PSTN for secure, always-on communications.
These links support:
- Status updates and condition monitoring
- SCADA systems and grid telemetry
- Fault detection and alarm triggering
- Predictive maintenance of critical infrastructure
The geography of energy infrastructure makes the PSTN switch-off particularly challenging. Remote substations and distribution points are often located in isolated, unmanned, or environmentally exposed locations. These sites were originally chosen for ease of grid connection—not for telecoms accessibility—so mobile and fibre coverage is often non-existent or cost-prohibitive to deliver.
Adding to this complexity is the fact that some legacy telemetry systems are line-powered, drawing their power directly from the PSTN copper line. Replacing these systems requires a complete rethink: a new communications pathway, a new power source, and ruggedised equipment that can operate in remote environments for years without on-site support.
Starlink as the Replacement
Starlink delivers robust connectivity that aligns well with these requirements:
- Low-latency broadband suitable for SCADA polling and event reporting
- A compact, weatherproof antenna that can be mounted on poles, enclosures, or rooftops
- The ability to run on battery power, with many sites already incorporating solar and UPS systems
- Rapid deployment time—installation is often completed within a day
Starlink’s independence from terrestrial infrastructure reduces the number of points of failure and ensures that monitoring and alert systems stay online even when fibre or mobile services are unavailable or down.
By integrating Starlink with edge computing devices or IoT gateways, utility providers can enhance their visibility into remote operations while future-proofing against further telecoms changes.
Water Infrastructure
Water utilities across the UK depend on PSTN for monitoring and controlling everything from treatment plants to remote pumping stations, stormwater overflows, and reservoir level sensors.
These systems are critical not only for efficiency and compliance but for public health and safety. In flood-prone areas, for example, early warning systems depend on real-time telemetry to inform emergency response teams and issue alerts to the public.
PSTN supports:
- Water quality and flow telemetry
- Level monitoring in reservoirs and tanks
- Automated pump controls and alarms
- Early flood detection systems
These systems often operate in challenging environments: riverbanks, coastal flood plains, high-altitude reservoirs, or underground pumping chambers. For many of these locations, the PSTN was the only cost-effective communications method that didn’t require new cabling or dedicated radio links.
Starlink as the Replacement
Starlink enables rapid and resilient connectivity for water infrastructure:
- Maintains always-on telemetry from distributed assets
- Operates even in extreme weather conditions—crucial for flood monitoring
- Offers a stable broadband backhaul for SCADA, remote PLCs, and smart sensors
- Reduces dependency on local telecoms infrastructure or 4G coverage
For real-time operations like treatment plant automation or pumping station response during storms, latency and uptime are paramount. Starlink offers sub-50ms latency and high throughput—more than enough for encrypted data transmission, alarms, and command-and-control systems.
Furthermore, Starlink’s performance enables future applications like AI-assisted leak detection, drone-based inspections, and cloud-based water management dashboards—all of which require dependable IP connectivity.
National Transportation Networks
The UK’s transport infrastructure relies heavily on PSTN for a variety of control and safety systems. Highway authorities and transport agencies use these connections for:
- Traffic signal controllers and loops
- CCTV monitoring of roads and junctions
- Variable message signs (VMS) and signage control
- Incident detection and automated alerts
In addition, railway infrastructure continues to use PSTN in specific areas for:
- Remote signalling support
- Track circuit monitoring
- Weather sensors and bridge condition alerts
The common theme across all these applications is the need for reliable, remote communication with unmanned field equipment—often deployed in roadside cabinets, gantries, or rail-side enclosures.
Starlink as the Replacement
Starlink is a strong fit for these types of systems:
- Quick-to-deploy connectivity for remote or mobile control points
- Compatible with VPN, SCADA, or other IP-based monitoring systems
- Can be integrated into roadside or trackside enclosures using compact, ruggedised mounts
- Ensures critical messaging and traffic control systems remain operational even if fibre or 4G services fail
In transport settings, uptime and responsiveness are critical. A missed alert or signal dropout could lead to traffic incidents or operational disruptions. Starlink’s reliable performance—even during storms or outages—adds a new layer of resilience to these systems.
Emergency Services Infrastructure
Emergency infrastructure—including fire and rescue, ambulance services, and police—relies on PSTN for high-reliability alarm monitoring and communications.
Typical applications include:
- Building alarms connected to emergency monitoring centres
- Emergency call points in lifts, public buildings, and isolated locations
- PSTN-connected panels in fire alarm or evacuation systems
The stakes here are high: system failure could lead to delayed emergency response or loss of life.
Starlink as the Replacement
Starlink provides:
- Backup or primary broadband for VoIP-enabled alarm panels and security systems
- Portable connectivity for mobile command units and temporary incident hubs
- Power-efficient operation that can be maintained on battery during outages
- Resilient links for community emergency alert systems in rural or coastal areas
Emergency services must remain operational even when traditional infrastructure fails. With Starlink, control rooms, ambulance depots, or rural fire stations can retain internet access during floods, network blackouts, or civil emergencies.
Telecare Services and Health Infrastructure
Approximately 1.8 million people in the UK depend on telecare services, many of which are built around PSTN lines. These services are essential for:
- Older people living independently
- Individuals with disabilities or chronic conditions
- Patients receiving remote monitoring or emergency support
These systems include fall detectors, personal alarms, motion sensors, medication reminders, and voice contact buttons.
Starlink as the Replacement
Starlink ensures telecare continuity through:
- High-speed, low-latency links to digital alarm receiving centres (ARCs)
- IP telephony support to maintain call quality and reliability
- Backup connectivity for digital care hubs and outreach teams
- Rapid deployment to rural communities where fixed broadband is not viable
As the switch to digital progresses, many care providers are moving to cloud-based platforms for case management, real-time data analysis, and video consultations. Starlink enables this transition—without relying on legacy DSL or spotty mobile coverage.
Local Authority Services and Community Impact
While national infrastructure faces significant adaptation, local authority-run services are also being heavily affected.
Social Housing and Care Settings
Many housing associations rely on PSTN for:
- Door entry and intercom systems
- Fire and carbon monoxide alarms
- Pull-cord systems and telecare units
- Lift phones and emergency call lines
These services protect some of society’s most vulnerable groups, and must remain operational 24/7.
Schools and Public Buildings
In schools, libraries, and community buildings, PSTN powers:
- Lift emergency phones
- Fire and intruder alarms
- CCTV and building management systems
- Utility meter reporting and vending systems
Any disruption to these services could cause compliance issues or endanger public safety.
Starlink as the Replacement
Starlink allows councils and housing associations to:
- Rapidly deploy new digital lines without installing fibre
- Maintain safety systems during terrestrial network failures
- Integrate smart systems like remote diagnostics, access control, and video intercoms
- Scale connectivity across multi-site estates with centralised management
For hard-to-reach properties or older buildings where retrofitting fibre is difficult, Starlink provides a clean, modern alternative that doesn’t compromise on uptime or regulatory compliance.
Device-Specific Impacts
The PSTN switch-off will affect thousands of specific device types:
- Lift Phones & Alarm Systems: Must be transitioned to IP and maintained during power cuts
- Telemetry Devices: Often installed in harsh environments; require rugged connectivity
- Test Equipment & Secure Labs: May need upgrades to ensure stable, secure transmission
- CCTV & Access Control: Must maintain video quality and reliability via digital links
Starlink can support these devices through:
- Integrated LTE/Starlink routers with failover logic
- Power backup integration for always-on operation
- VPN or SD-WAN support for secure data handling
Power Resilience: A Critical Consideration
One of the defining features of PSTN was its line-powered reliability. Even during power cuts, many systems remained active thanks to the voltage supplied via the copper line.
Digital alternatives—including fibre, mobile, and satellite—all require external power. This adds a new layer of complexity, particularly for remote or unmanned installations.
Starlink Supports Power Resilience Through:
- Operation on low wattage (typically ~50–75W)
- Compatibility with UPS systems, solar arrays, or remote battery packs
- Minimal environmental requirements—no fixed mast or tower needed
- Optional integration into solar-powered telecom enclosures or off-grid cabinets
By ensuring power and connectivity are both resilient, Starlink restores the confidence once associated with PSTN-connected systems.
Conclusion: Navigating the PSTN Switch-Off with Starlink
The decommissioning of the Public Switched Telephone Network by 2027 represents one of the most significant infrastructure transitions in recent UK history. With over 300 identified use cases spanning critical national infrastructure and essential local services, the scale of this challenge cannot be overstated. Energy networks, water systems, traffic management, emergency services, and telecare all face substantial adaptation requirements as their long-established communication channels are replaced.
The central challenge remains power resilience – transitioning from self-powered PSTN connections to digital alternatives creates new vulnerabilities in systems that must remain operational during emergencies. Solutions like Starlink Mini offer promising alternatives for critical applications, providing independent communication channels that can operate on battery power when primary systems fail. Particular attention must be paid to services supporting vulnerable populations, such as the 1.8 million telecare users whose safety depends on reliable communications.
While the PSTN switch-off presents significant challenges, organizations that approach the transition strategically may find opportunities for modernization and enhanced capabilities through digital alternatives. The path forward requires collaboration between infrastructure operators, service providers, technology suppliers, and regulatory bodies to ensure this massive transition maintains or enhances the resilience of the UK’s essential services, rather than compromising it.
Starlink provides a viable and proven replacement, offering:
- True geographic reach
- Low-latency, high-availability performance
- Rapid, flexible deployment
- Integration with legacy and modern systems alike
By incorporating Starlink into PSTN replacement planning, public and private sector leaders can maintain continuity, reduce downtime, and future-proof their most essential services.
Sources:
- UK Gov (DSIT) – “UK transition from analogue to digital landlines” (Guidance updated Feb 2024) gov.uk gov.uk
- Wikipedia – “Public switched telephone network – Service retirement (UK)” en.wikipedia.org
- Openreach – Corporate site info: “Retiring the analogue phone network by Jan 2027” openreach.co.uk
- BT Business – “Your guide to the PSTN switch-off” (2025)business.bt.com business.bt.com
- ChannelX (Tech news) – “UK PSTN Stop Sell Sept 2023 – impact on alarms, EPOS, CCTV, etc.” channelx.world
- UK Gov (DSIT) – Guidance on devices on phone lines (lift alarms, payment terminals) gov.uk
- LGA (Local Govt Association) – Digital Switchover Hub (Implications for telecare and traffic systems) local.gov.uk local.gov.uk
- LGA – Landline Switchover Readiness Survey 2022 (telecare usage and council prep) local.gov.uk local.gov.uk
- Ofcom – Statement on supporting vulnerable customers in digital phone migration gov.uk
- Starlink (SpaceX) – Starlink Network Updates (Latency improvements, ~20–30 ms goal) starlink.com
- Starlink website – Product info (Starlink “Mini” specs: >100 Mbps, DC power input) starlink.com
