The dates you need to be aware of with the ‘Big switch off’

As the ‘Big switch off’ of ISDN (Integrated Services Digital Network) and PSTN (Public Switch Telephone Network) lines approaches, it’s important for phone users to know where they stand. In this article, we’ll let you know the dates you need to be aware of, what happens on those dates, and how to prepare for a switch to fully digital communication.

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As with the life cycle of most tech innovations; they arrive, are often met with skepticism, become integrated into widespread use, and are eventually replaced by superior models. 

We’ve had access to landline telephones since the late 19th century. They’ve gone through many iterations from switchboards, to home-use and finally mobile phones. 

Each reinvention allowed us to bridge a communication gap, whether that was letter writing, long distance calling or the ability to make calls to and from anywhere in the world.

With the ‘Big Switch off’, the century old landline system that has served both business and consumer landlines - will be shut down. In its place a fully digital model, set to move communication into a new world of flexibility and customisation. 

What is the ‘Big switch off’?

The ‘Big Switch Off’ is the name given to the BT Openreach shutdown of ISDN and PSTN landline connections.

The first phase of this movement has already happened, with providers no longer offering PSTN landlines to consumers. This will be followed in spring 2025, with the complete termination of both PSTN and its business equivalent ISDN.

We’ll run down the specific dates a little later, however for businesses and consumers who haven’t reviewed their digital option, now is a good time to take a look at what’s on offer.

Why is it happening?

Although there are several reasons, a key factor is that PSTN and ISDN lines are simply too difficult to maintain. They run on a network of copper wires which span the length of the UK; a system that is both tricky and expensive to sustain.

VoIP technology, unlike traditional phone lines, allows users to make calls using the internet. This means businesses and consumers  no longer need to be tethered to one location, opening up a whole new avenue of possibilities for businesses and their employees. 

With VoIP services offering a flexible, simple and affordable model, traditional landlines can’t match the benefits of this new communication model.

Who will it affect?

The switch off will have an impact on everyone who uses landline connections to communicate. Although some users have already moved to digital services, both consumers and business owners need to be mindful of the approaching shutdown.

In some countries, the termination of ISDN and PSTN lines has already happened, with the UK and other European locations not far behind.  

Those who used software like Zoom during the pandemic are likely familiar and accustomed to the way VoIP works. However, as the rest of the world rolls out these digital replacement services, it’s vital that providers ensure that the less technologically-aware aren't left behind.

What can you do to prepare?

Switching  to a new provider can be daunting. It’s reassuring to know then, that VoIP is designed to be easy to set up, manage and maintain. There are however, a few things to consider before taking the leap into digital comms.

How to prepare as a consumer

For consumers still using PSTN, you'll need to look into what VoIP products are available. These services give you the same functionality that your landline does, but without the need for a PSTN connection.

Speak to your current provider to find out if they offer similar services. As with your landline, it’s worth shopping around providers to ensure you get value for money. For example, your choice might hinge on built-in features, ease of set-up or level of customer support.

How to prepare as a business 

Similarly, any business with telephony at their core should review their options. The good news is, broadband based VoIP services offer a host of advantages. This includes not having to tether your business to one location, making remote working simpler.

Whether business or consumer, a key requirement is a strong broadband connection. For optimum performance and less call dropouts, your connection should offer between 10-50 Mbps download and 3-20 Mbps upload speeds.

Aside from speed, it’s down to the needs of a business to determine which service suits you best. The majority of VoIP services are easy to scale and offer a variety of integration options. This means they have the scope to grow alongside your business.

While the VoIP market is packed with great services, not every provider of landline connections is guaranteed to offer VoIP services. If your provider isn’t one of them, don’t worry;  we’ll talk you through some of the standout options in the next section.

What services are available to help you?

When making an investment in something as essential as communication tech, it’s worth asking yourself: What do I need from this service? 

VoIP for consumers

Consumer grade VoIP is the simplest option to gauge. Services like EE’s digital phone deliver HD quality calls over your broadband connection, with handy features like 3-way calling and specific caller identification available. 

For added flexibility, providers like Vonage offer mobile apps for IOS, Android and Windows - allowing users to access their home phone number anywhere.

VoIP for business

VoIP business systems range from smaller yet powerful models, to larger systems, capable of dealing with increased call volume and user capacity.

For smaller businesses, 8x8 offers a phone system that can handle demand, while being easily scalable too. From call recording to a host of integrations - it offers you the advantages of a larger telephony set-up for a reduced price.

Companies with a sizable workforce may prefer a unified communication service like T2K’s Gamma Horizon. These services come fully equipped for the modern call center, with CRM integration, cloud-based video and audio communication and call management tools to ensure a smooth customer journey.

What are the dates you need to be aware of?

We don’t want you to miss anything in your switch to digital communication. That’s why we’ve compiled all of the key dates in the lead up to 2025’s ‘Big Switch Off’.

  • 5 September 2023: As of September 2023, providers stopped offering landline connections. This means that customers calling to request this have been told about the switch off, and offered an alternative digital service.
  • 31st December 2025: At the end of 2025, all PSTN and ISDN lines will be shut down. This means all copper wire telephony services will be terminated and switched for fully digital communication.
  • 1st January 2026: With the ISDN and PSTN shutdown complete, all phone-based communication will use VoIP technology going forward.
  • Early 2033: As laid out in the ‘Level Up The UK’ plans, the government aims to have gigabit-capable broadband available nationally. This will ensure the future of VoIP communications is stable and reliable for consumers and businesses.

Why you should put these dates in your diary

Now that phone providers have stopped selling landline connections, it’s important for you to know when different stages of the shutdown are occurring.

This will give you time to make decisions on what VoIP services are suited to your needs, whether you’re looking to keep your landline, or to empower your workforce.

If you’d like to know more about the ‘Big Switch Off’ or have questions around what VoIP services are available, talk to T2K today. Our knowledgeable team can support you in finding a system that makes sense for your home or business. 

Lee Clarke
Sales Director

Having worked for T2k for nearly 25 years, it's fair to say that Lee is an expert when it comes to all things telephony and business communications. Overseeing the commercial side of the business, he has helped the company evolve and grow through the decades. In recent years, and with the advent of VoIP and hosted telephony, Lee has made sure that T2k is at the forefront of technological developments. With a firm interest in helping businesses navigate the world of telecoms, Lee is responsible for the majority of the content on this website.

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