Are you Ready for the ISDN Switch-Off?

Don’t get caught out.

Is your organisation prepared for the planned switch off of all ISDN and analogue lines by 2025? 

Once the planned BT switch off comes into effect, you will no longer be able to make calls utilising traditional analogue systems and ISDN lines.

Learn more about ISDN lines.

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What is an ISDN Line?

ISDN stands for Integrated Services Digital Network. It’s a telecommunications technology that enables the transmission of digital data over traditional phone lines. ISDN lines were crucial for organisations needing reliable and relatively fast data transfer.

ISDN offered several advantages over traditional analogue phone lines, such as faster data transfer speeds, better voice quality, and the ability to transmit both voice and data simultaneously over the same line. It was commonly used for services like video conferencing, internet access, and transferring large files.

But now with the widespread adoption of internet technologies like Voice over IP (VoIP) telephony, ISDN has become less common and no longer the preferred method of voice communication. 

The widespread adoption of VoIP phone systems has shifted the telecommunication structure for businesses worldwide, prompting the planned switch off of ISDN lines by 2025.

What is the ISDN Switch Off?

The ISDN switch-off refers to the planned phase-out of the ISDN network, a move initiated by telecommunication companies, including BT, as they shift towards more modern, efficient technologies such as Voice over IP (VoIP). This transition marks a significant change from the traditional analogue phone systems and ISDN lines towards digital communication solutions. The process involves gradually disabling ISDN services, effectively ending the reliance on physical line rental and analogue systems for voice and data transmission. This move is intended to modernise the telecommunications infrastructure, offering businesses and consumers more flexible, cost-effective, and feature-rich alternatives for their communication needs.

How do I Know if my Business Uses ISDN Lines?

To determine if your business has an ISDN line, you can take a few steps:

  1. Check with Your Telecommunications Provider: Contact your telecommunications provider or IT department and enquire about the type of phone lines your business is using. They should be able to tell you whether you have ISDN lines or if you’re using another type of technology, such as digital service like VoIP.

  2. Look at Your Phone System: If your business has a phone system installed, check its documentation or consult with the person responsible for managing the phone system. They should know whether the system is connected to ISDN lines or another type of service.

  3. Check for ISDN Equipment: ISDN lines require specific equipment to operate, such as ISDN terminal adapters or ISDN-compatible routers. If you have any of these devices installed in your office, it’s likely that your business is using ISDN lines.

  4. Review Billing Statements: Review your telecommunications billing statements. They often include details about the type of services and lines you’re subscribed to, which can help you determine if ISDN lines are in use.

  5. Consult with an IT Professional: If you’re unsure about the type of phone lines your business has or how to identify them, consider consulting with an IT professional or telecommunications specialist. They can assess your setup and provide guidance on the type of lines you’re using.

By taking these steps, you should be able to determine whether your business has ISDN lines or if you’re using another type of telecommunications technology.

How Will The ISDN Switch-Off Affect Your Business?

The ISDN switch-off will fundamentally transform how businesses across the UK communicate, compelling a shift from traditional PSTN (Public Switched Telephone Network) and ISDN (Integrated Services Digital Network) lines to more advanced technologies like voice over internet protocol (VoIP) and Session Initiation Protocol (SIP) trunking. This transition is not just about changing your business phone system; it’s about upgrading to a more flexible, scalable, and cost-effective communication solution. With the decommissioning of ISDN, businesses will no longer be able to rely on these outdated systems for their voice and data transmission needs.

Instead, the adoption of VoIP technology, facilitated by broadband internet, offers enhanced features such as call recording, virtual meetings, and mobile app integration that are not available with traditional phone systems. This means that businesses will need to switch to a VoIP-based system to maintain and potentially enhance their communication capabilities. The reliance on broadband for VoIP services highlights the necessity for a robust and reliable internet connection, urging businesses to evaluate and possibly upgrade their current broadband service to ensure optimal VoIP performance.

For businesses that have not yet transitioned from PSTN and ISDN, the switch-off represents a critical juncture to review and update their current phone system. This transition period offers an opportunity to not only comply with the new telecommunication standards but also to harness the benefits of modern communication technologies, leading to improved operational efficiency and customer service.

Benefits of Switching from ISDN to VoIP

Cost Savings

Save costs on local and international call rates, as well as making savings on physical equipment maintenance costs.

Great Flexibility

With a VoIP business telephone system, your business can scale up or down with ease, depending on your needs. Providing a great level of flexibility that will allow you to adjust as your business grows and changes. With

Secure Communication

Unlike traditional landlines, VoIP systems are designed to be secure and reliable. With built-in encryption protocols and other security features, such as two-factor authentication, you can ensure your business communications are kept private and secure.


With VoIP services, your users will be able to easily access their business contacts, make and receive calls, send business SMS messages and host/attend conference calls with colleagues, clients and suppliers from their desktop or mobile device.

  1. Secure Internet Connection: Crucial for safeguarding sensitive voice data from unauthorised access or interception.
  2. Vulnerability to Cyber Threats: Without proper security measures, VoIP networks are susceptible to eavesdropping, data breaches, and service disruptions.
  3. Mitigation of Risks: Implementation of encryption, firewalls, and regular security updates helps mitigate these risks.
  4. Ensuring Privacy, Integrity, and Availability: Security measures ensure the privacy, integrity, and availability of communication channels.
  5. Business Protection and Compliance: Prioritising a secure internet connection helps businesses protect their communication infrastructure and maintain regulatory compliance.
  1. Softphones: Softphones are software applications installed on computers, smartphones, or tablets, turning these devices into VoIP endpoints. They often feature intuitive interfaces for making calls, accessing contacts, and managing voicemail.

  2. VoIP Gateways: VoIP gateways bridge the gap between VoIP networks and traditional telephone systems, enabling communication between IP-based and legacy analog or digital systems.
  3. VoIP Conference Phones: These specialised devices are optimized for group communication, featuring enhanced audio quality, microphone arrays, and speaker systems suitable for conference rooms or meeting spaces.
  4. IP Phones: These resemble traditional telephones but connect directly to the internet, often via Ethernet cables or Wi-Fi, allowing users to make and receive VoIP calls.

  1. Seamless Transition: Partnering with an experienced VoIP provider ensures a smooth transition to VoIP technology.
  2. Extensive Knowledge and Expertise: Experienced providers bring extensive knowledge, expertise, and technical support to tailor solutions to specific business needs effectively.
  3. Proactive Monitoring and Troubleshooting: Providers offer proactive monitoring, troubleshooting, and security measures to safeguard communication data and minimise disruptions.
  4. Optimisation of Network Performance: Experienced providers advise on best practices to optimise network performance, ensuring efficient communication.
  5. Integration of Advanced Features: Providers integrate advanced features seamlessly, enhancing efficiency and productivity within the organisation.
  6. Enhanced Efficiency and Productivity: Partnering with an experienced VoIP provider enhances efficiency and productivity by leveraging their expertise and support.
Features & Functionality
  1. Call Routing: VoIP systems enable flexible call routing options, allowing calls to be directed to specific extensions, departments, or devices based on predefined rules or criteria.
  2. Auto-Attendant: VoIP systems can utilise auto-attendant features to greet callers, provide menu options, and route calls to the appropriate destination without human intervention.
  3. Call Recording: VoIP systems support call recording functionality, enabling users to record and store conversations for quality assurance, compliance, or training purposes.
  4. Mobile Integration: VoIP systems offer seamless integration with mobile devices, enabling users to make and receive calls, access voicemail, and utilise other features while on the go.
  5. Unified Communications: VoIP systems integrate with other communication tools and applications, such as email, instant messaging, and collaboration platforms, creating a unified communication environment for enhanced productivity and collaboration.
  1. Importance of Security: Security is paramount within VoIP phone systems to protect sensitive communication data.
  2. Vulnerability to Cyber Threats: Without adequate security measures, VoIP networks are vulnerable to various cyber threats, including eavesdropping, data breaches, malware attacks, and denial-of-service (DoS) attacks.
  3. Mitigation of Risks: Implementing robust security protocols, such as encryption, firewalls, intrusion detection systems, and regular security updates, helps mitigate these risks.
  4. Protection Against Cyber Attacks: Security protocols safeguard communication data from unauthorised access, interception, or tampering.
  5. Continuous Security Measures: Regular security updates and proactive monitoring are essential to maintain the effectiveness of security measures within VoIP systems.

Getting Started with VoIP

There are a few essential components that you will need to get started successfully with your VoIP phone system, these include:

  1. Internet Connection: A stable and reliable internet connection is crucial for VoIP communication. Ensure that your internet service meets the bandwidth requirements for VoIP to ensure clear and uninterrupted voice calls.

  2. VoIP-Compatible Devices: You’ll need VoIP-compatible devices such as IP phones, softphones (software-based phones), or adapters for traditional analog phones to connect to the VoIP network.

  3. VoIP Service Provider: Partnering with a reputable VoIP service provider is essential for seamless implementation and ongoing support. A VoIP provider offers the necessary infrastructure, software, and technical expertise to set up and manage your VoIP system effectively.

  4. Features and Functionality: Consider your business communication needs and choose a VoIP provider that offers features such as call routing, voicemail, conference calling, and mobile integration. Customisable features can enhance productivity and collaboration within your organization.

  5. Security Measures: VoIP systems transmit data over the internet, making security a priority. Ensure that your VoIP provider implements robust security measures to protect your communication data from unauthorized access and cyber threats.

Partnering with an experienced VoIP provider is crucial to the success and efficiency of your business communication infrastructure. An experienced VoIP provider brings a wealth of knowledge, expertise, and technical support to the table, ensuring a smooth transition to VoIP technology and ongoing reliability. With their in-depth understanding of VoIP systems, they can tailor solutions to meet your specific business needs, optimise network performance, and integrate advanced features seamlessly.

Why Choose D&A Media for Your Business VoIP Phone System

D&A Media are a UK VoIP provider experienced in helping businesses transition to a VoIP phone system. We provide an all-in-one solution that includes hardware, internet connection, software and 24/7 technical support for setting up and managing your new system.

We understand how important it is for businesses to have reliable communication systems and our team of experts are here to help you every step of the way. From choosing the right system for your business to configuring and deploying it, we make sure that everything is set up correctly so you can get the most out of your VoIP phone system.

With 30 years of experience working with leading VoIP providers, D&A Media has the expertise and capabilities to provide your business with a reliable VoIP phone system that can help drive productivity and keep customers connected.

Contact us today to learn more about our VoIP phone systems and how we can help you transition to a modern communication system.


Will I lose my number with the ISDN switch off?

No, you will not lose your number with the ISDN switch-off. One of the significant advantages of making the migration from ISDN to using VoIP for your business communications is the ability to keep your existing phone numbers. This seamless transition means there will be no disruption in how your customers reach you. The switch to VoIP essentially enhances your ability to make phone calls over the internet, providing superior flexibility and cost-efficiency without the need to change contact information. This feature is particularly beneficial for businesses looking to maintain brand consistency and minimise the inconvenience to clients during the migration process.

Can you make the switch from ISDN to VoIP before 2025?

Your business can make the switch from ISDN to VoIP before the 2025 ISDN switch-off deadline. This proactive measure not only ensures that your company is ahead in maintaining modern business communications but also leverages the benefits of transmitting voice data via the Internet. Transitioning to VoIP ahead of time means your business will need to make necessary adjustments, but doing so allows for a smoother adaptation to the new system, without the pressure of an impending cutoff. It’s a strategic move to ensure your business communications are not disrupted and continue to benefit from the latest technological advancements in voice and multimedia data transmission.

What will replace ISDN and PSTN?

VoIP (Voice over Internet Protocol) technologies will replace ISDN and PSTN lines for UK businesses. This transition represents a significant shift in how companies communicate, offering a more flexible, scalable, and cost-effective solution. VoIP allows for the transmission of voice and multimedia content over the internet, providing clearer call quality, enhanced security features, and the ability to integrate with various business applications. UK companies looking to future proof their business will need to upgrade to VoIP systems as the switch-off of ISDN and PSTN lines approaches. This evolution in telecommunications ensures that businesses are equipped with the latest technology to meet their communication needs efficiently and effectively.

What Our Customers Say...

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