Guidance

Communication providers: ensuring telecom services are resilient

Published 22 August 2025

Overview

Telecommunications are a vital part of the UK’s Critical National Infrastructure (CNI) that supports:

• emergency services and public safety
• business operations
• daily life, whether working, accessing services, or staying connected with family and friends

As more activity moves online and digital services continue to evolve, the resilience of telecoms networks is increasingly essential.

The government works in partnership with communications providers to ensure that networks remain secure, resilient, and accessible, including during emergencies. This approach supports the objectives set out in the UK Government Resilience Action Plan, which highlights the importance of strengthening the systems and infrastructure that people and services rely on most.

This information below sets out:

• what communications providers must do to ensure their services are appropriately resilient
• the role of Ofcom as the independent regulator
• the support in place for vulnerable customers
• advice about what happens if there is disruption and how to prepare for emergencies
• how to resolve issues and make complaints

Responsibilities of communications providers

In relation to the resilience of their networks and services, communication providers in the UK are legally required to:

• Ensure the security, integrity, and availability of their networks and services under the Communications Act 2003 and the Telecommunications (Security) Act 2021. This includes taking appropriate and proportionate steps to identify risks to their resilience, reduce those risks, prepare for compromises and mitigate and remedy them when they do occur.
• Maintain uninterrupted access to emergency services (999 and 112), even during power outages or network failures.
• Comply with Ofcom’s General Conditions of Entitlement, which include specific obligations to support vulnerable users and ensure service continuity.
• Providers designated as Operators of Essential Services (OES) under the Network and Information Systems (NIS) Regulations 2018 must take appropriate steps to secure their networks and minimise the impact of incidents.

Providers must:

• report major network outages or incidents that significantly impact service availability. This obligation is set out in Ofcom’s General Conditions of Entitlement (Condition A3) and the Telecommunications (Security) Act 2021, which require providers to notify the regulator of serious disruptions and take appropriate remedial action
• guarantee access to emergency services for at least one hour during a power outage for customers who rely solely on landlines. Offer this solution free of charge to those customers
• communicate clearly with customers about any risks or changes to their service, especially during transitions like the Public Switched Telephone Network (PSTN) switch-off

They are also expected to:

• implement backup power systems at key infrastructure points (such as fibre cabinets and exchanges)
• participate in cross-sector coordination with energy providers and government to prioritise restoration of services during outages. This includes supporting local and national response arrangements where required under the Civil Contingencies Act 2004, which sets out legal duties for cooperation and emergency preparedness

How this is overseen

Ofcom is the independent regulator for the UK’s communications sector. It plays a central role in ensuring that communications providers meet their legal obligations and that networks remain secure, resilient, and accessible including during emergencies.

Ofcom is responsible for:

• setting and enforcing rules for communications providers, including those related to:

  • network security
  • service continuity
  • support for vulnerable users
• monitoring network resilience and emergency access. Ofcom publishes information in its annual Connected Nations report, providing data, insights and trends on the availability, performance, and resilience of UK telecoms infrastructure
• investigating failures and issuing penalties where providers fall short of their obligations. Ofcom has the power to compel information, assess compliance, and take enforcement action, including issuing financial penalties where necessary

Its powers are set out in the Communications Act 2003 and were significantly strengthened by the Telecommunications (Security) Act 2021, which introduced new duties on providers to identify and reduce risks to their networks and services.

Ofcom also provides technical guidance measures it expects communications providers to take to ensure the resilience of their networks and services. These include outcome-based principles and specific technical measures - such as power backup, network architecture, and operational practices - which providers are expected to implement as appropriate and proportionate steps to meet their legal duties. Read further information on Ofcom’s work on resilience.

Supporting vulnerable users

Ofcom’s guidance on treating vulnerable consumers fairly suggests measures providers could adopt to help make sure they treat vulnerable people fairly and give them the help, support and services they need.

This includes:

• measures in areas such as establishing and publishing policies and procedures for treating vulnerable customers fairly
• identifying vulnerable customers; recording information about vulnerable customers’ needs
• communicating with vulnerable customers
• staff training and resources
• monitoring and evaluating success

The government has also worked with the telecoms industry to introduce new protections for vulnerable users during the migration to digital phone lines. These measures include commitments to maintain access to emergency services and provide backup solutions for those who rely solely on landlines or telecare devices. These can be found on the PSTN pages.

The upgrade from PSTN to digital technologies

The PSTN is the UK’s traditional analogue phone network. It is being phased out and replaced with digital services using Voice over Internet Protocol (VoIP). This transition is expected to be completed by January 2027. Find guidance on the PSTN migration here.

What happens if there is disruption and how to prepare for emergencies

How you can prepare for phone and broadband outages

While communications providers are legally required to ensure the resilience of their networks, outages can still occur due. The government’s Prepare campaign website provides practical advice to help individuals and households prepare for a range of emergencies and hazards, including disruptions to phone and broadband services.

The advice outlines steps to take before and during an outage, including:

• understanding your landline’s resilience: If you rely solely on a landline or telecare device, contact your provider to check whether your equipment will function during a power cut. Providers may offer a free backup solution to ensure emergency access.
• planning for vulnerable users: consider how neighbours or local community members could assist during an outage, particularly for those who live alone or rely on connected health devices.
• staying informed: keep a battery-powered or wind-up radio and note down key radio frequencies in case internet-based services are unavailable
• offline navigation: download or print maps in advance, as most mobile navigation apps require internet access even if GPS is available

The site also encourages households to include telecoms disruption in their broader emergency planning. For full guidance, visit: prepare.campaign.gov.uk – phone and broadband outages.

Power cuts or storms  and access to 999

Communications networks are designed to be resilient, but events such as severe weather, power cuts, and technical faults can sometimes cause disruption. Providers may use backup power systems to keep services running, deploy portable generators or emergency engineers to affected sites. Services typically resume immediately once electricity services are restored.

In the event your mobile network is unavailable, all emergency 999 calls made from mobile phones will automatically switch to an alternative network. This ensures that even if your mobile network is down or has poor signal, your emergency call can still go through by using another available network.

Most disruption is usually short and relatively localised, but for major regional or national incidents the government works in partnership with industry through the Electronic Communications Resilience and Response Group (EC-RRG) to coordinate the response, and can use the National Emergency Alerts for Telecoms (NEAT) to support that where appropriate.  Beyond incident response, EC-RRG also plays a proactive role in promoting good resilience practices across the sector - supporting preparedness, recovery planning, and continuous improvement.

Providers must:

• guarantee access to emergency services for at least one hour during a power outage for customers who rely solely on landlines. This is often accomplished through a battery back-up
• offer this solution free of charge to those customers
• communicate clearly with customers about any risks or changes to their service, especially during transitions like the PSTN switch-off

They are also expected to:

• implement backup power systems at key infrastructure points (e.g. fibre cabinets, exchanges)
• participate in cross-sector coordination with energy providers and government to prioritise restoration of services during outages
• provide wherever possible tow to site generators to masts and other infrastructure

If you can’t access 999 or have phone or broadband Issues

Although most people call 999 from a mobile or landline phone, there are other ways to contact the emergency services for those unable to use those. These include:

Emergency SMS

• register in advance by texting ‘register’ to 999
• Once registered, you can text 999 in an emergency
• Use this method if you’re in danger and can’t speak

British Sign Language (BSL)

• BSL users can use the 999 BSL app or 999 BSL website for emergency video relay

If you use a landline phone service that relies on the internet - such as Voice over Internet Protocol (VoIP) - you may not be able to call 999 during a power cut or if your broadband connection fails. To ensure continued access to emergency services, communications providers are required to offer a back-up solution that enables calls to 999 for at least one hour during a power outage. This must be provided free of charge to customers who rely solely on their landline.

One common solution is a battery back-up unit (BBU). These devices are compact, easy to install, and can power a broadband router for several hours—typically between 4 and 7 - depending on the equipment and usage. Some models include a hibernation feature that reserves part of the battery for emergency use, helping to ensure that access to 999 is maintained during prolonged outages.

If you rely on a landline ,contact your provider to check whether your equipment will function during a power cut and what back-up options are available. It is also advisable to have an alternative means of contacting emergency services, such as a mobile phone.

Your phone should automatically connect to another available network if your provider’s signal is unavailable, but if you can’t get through to 999 on your mobile:

• try calling 112 – it works the same as 999 and may connect even if 999 doesn’t
• move to a different location if possible – signal may improve outdoors or at higher ground

Users with an ongoing issue or complaint

Complaints

If you’re experiencing an ongoing issue with your phone or broadband service, your first step should be to contact your provider directly. They are responsible for resolving service problems and should have a formal complaints process in place.

Compensation

You may be entitled to compensation if your landline or broadband service is delayed, disrupted, or if an engineer misses an appointment. Several providers have signed up to Ofcom’s compensation scheme, which ensures customers receive payments for delayed repairs, late service activation, and missed appointments. The level of compensation is reviewed annually.

Dispute resolution

If your complaint isn’t resolved after 8 weeks - or sooner if you receive a “deadlock letter” - you can escalate it to an independent Alternative Dispute Resolution (ADR) scheme. From 8 April 2026, this period will reduce to 6 weeks.

Communications providers offering services to individuals, small businesses (up to 10 employees), and not-for-profit organisations (with up to 10 staff, excluding volunteers) must be members of an ADR scheme. ADR schemes are free to use and can require the provider to take action to put things right - amongst other things, this might include compensation, practical steps to fix the issue, cancelling an account, issuing an apology, or recommending changes to prevent the problem from recurring.

You can check with your communications provider to find out which scheme they belong to. Alternatively, you can find out through the following websites:

• Communications Ombudsman
• Centre for Dispute Resolution - CISAS (CEDR)
• Ofcom information about ADR

Ofcom’s role in complaints

You can also report serious or repeated failures to Ofcom, the UK’s communications regulator. Whilst they do not investigate individual complaints about phone or internet services, they monitor trends in the issues consumers raise with them and might take action where providers are not meeting their legal duties.