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Digital Voice and the landline phone switch-off: what it means for you

You may have heard of BT Digital Voice, the PSTN switch-off, or that landline phones are being replaced. We explain all you need to know about the upcoming changes
Yvette FletcherPrincipal researcher & writer

It's arguably the biggest social project since analogue television was retired some 10 years ago: the UK's telephone network is also going digital. The telecoms industry has even set a deadline that's backed by the UK government – the old copper network will be switched off at the end of 2025.

These changes will affect everyone who has a landline they'd like to keep using; soon these will all work via a broadband connection instead. It's absolutely essential that the migration to digital landline services is done well so that those who depend on their landline always have access to a reliable service - but there have already been several stumbles along the way. 

Read on to learn what the PSTN switch-off will mean for traditional landline services and for you.

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What is Digital Voice? 

Digital voice services are the future of landlines – they work using broadband connections rather than copper phone lines.

Digital Voice is the name BT, the UK's biggest landline provider, uses for its digital voice service. You may also hear digital voice services referred to as 'VoIP', 'IP voice' and other branded versions such as 'Sky Voice' or 'TalkTalk Voice'

What does PSTN mean? 

PSTN stands for public switched telephone network – it's the copper phone network that delivers analogue landline phone services. The plan is for it to be switched off at the end of 2025 and for all landline services to be offered digitally.

The UK isn’t the first country to make this move. Estonia and the Netherlands have already switched off their PSTNs, and France, Germany and Japan are just some of the other countries that are also in the process of winding theirs down.

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Why are traditional phone services being taken away? 

The phone network that has existed since the Victorian era is coming to the end of its life. While its physical infrastructure remains similar to when it was installed, our communication needs have changed immensely. Alongside this, broadband connections rely increasingly on fibre optic networks. These not only offer faster speeds than copper but are also more reliable, more resilient and easier to maintain. Find out more about how fibre broadband and standard broadband compare in our guide to the benefits of fibre broadband

The demise of the PSTN is linked to the roll-out of full fibre broadband in the UK, although the two aren't on the same timeline. While phone services will no longer use the copper network by the end of 2025, the aim is for full fibre coverage to reach 85% in the same year.


The traditional phone network isn't the only communications infrastructure that's being modernised – read about the UK 3G network switch-off, and what it means for you. 


When will my landline be switched off?

Your landline provider will get in touch with you when it's coming to the time for you to migrate. They might call the new service Digital Voice, IP voice or a branded version such as 'Sky Voice'. 

BT has already migrated hundreds of thousands of customers to its Digital Voice service. Initially it (and other providers) mainly focussed on offering digital phone services to customers when they switch broadband providers or upgrade to full fibre broadband. Now when you switch provider, you may also be offered the option to eschew a phone line altogether – previously something only offered by a handful of providers.

However now, BT is now migrating more fixed broadband customers to its Digital Voice service in a region-by-region roll out. It is focussing on customers who are most ready to switch, so vulnerable customers (including those with a healthcare pendant), landline-only customers and those in areas with no mobile reception won't be proactively switched for now. Customers will be contacted four weeks before they are migrated, so there shouldn't be any surprises.

If you don't want to change to a digital phone service, in many cases you won't have to upgrade just yet: traditional phone services will continue to work for a couple of years. But traditional phone services won't be offered to new customers, and by December 2025 they will be withdrawn entirely. 

There is also a chance you may be migrated sooner if the infrastructure in your local area fails, as malfunctional copper lines and phone exchanges aren't being replaced.

How do digital voice services work?

Digital phone services work using something called Voice over Internet Protocol (VoIP). Your broadband/landline provider might also call it IP voice or Digital Voice.

VoIP converts your voice into a digital signal, so that it can be sent between computers and other devices on the internet. It's the same technology that's used by popular video and voice messaging services like FaceTime, Skype and WhatsApp. 

However, you won't need to use these sorts of applications to make calls – many landline phones are already compatible. In practical terms, most people won't notice the difference compared to making and receiving calls through a traditional landline.

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What are the benefits of the move to digital voice services?

The move to digital phone services isn't only about infrastructure: it also offers benefits such as clearer calls, the ability to make multiple calls simultaneously and the possibility of accessing your landline in other locations. 

In time, it will also allow telephone providers to develop tools to better protect their customers against scam and nuisance calls. 

What are the risks of the move to digital voice services? 

There are a million UK voice-only customers, some of whom will not have any access to broadband. People in this group are more likely to be older, financially vulnerable, not working or from lower socioeconomic groups. There is also a risk that certain devices that currently rely on a phone line won't work if the line is a digital one – plus, digital services won't always work if there's a power outage.

Ofcom told us it that will keep a close eye on the progress made by phone providers to help ensure all customers, particularly those who are vulnerable, are supported through the transition. The UK government has also called for phone providers to protect vulnerable customers and ensure they have access to emergency services during power outages.

But there have been a few stumbles along the way. BT has had to pause and restart its Digital Voice migration after customer complaints about service loss during power outages. Ofcom has also announced an investigation into Virgin Media's migration, citing concerns around its treatment of vulnerable customers.

Which? wants to make sure that all consumers across the UK are able to move over to these new connections as smoothly as possible. We're working with Ofcom and industry to ensure that they provide clear, transparent and easy-to-understand information to consumers about the process. 

What will happen when I am moved to digital voice services?

In most cases, the changeover will be simple. While some phones might require an adaptor, many will continue working (particularly DECT cordless phones) – you'll just have to plug yours into your router or a new socket.

Older phones might need to be replaced. It's likely that providers will offer a new model, but it might come at a cost. Some people might need a new or upgraded router, supplied by their provider. 

Once set up, your phone will work in much the same way it always has. You'll be able to keep the same phone number and will still hear a dial tone when you lift the handset. 

You'll also still have to pay for calls in the same way – that's even the case if they're delivered using your broadband connection. 

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How will digital voice services be connected to my home?

If you’re simply migrating to a digital phone line without upgrading to full fibre, then there won’t be any change to the physical infrastructure. Your service will work using the wiring that’s already in place - it’ll simply be a case of connecting your phone via your router.

Upgrading to full fibre services has more of an impact because fibre optic cables need to be installed through to your home. An engineer visit will always be required to set up the service which will be connected using either overground or underground cables. 

Openreach told us that just over half of properties can be connected using existing telegraph poles – a line from the pole will then be attached to your home. But in other cases, the fibre optic cables will be delivered underground through to an external wall of your property. Openreach uses several different techniques to minimise disruption to the property – it has tools that can burrow underneath a driveway or garden, so you don’t need to worry about a large trench being dug through your patio.

In both cases, the engineer will also need to drill a small hole in an outside wall of your property to allow you to connect up to the service.

Will my existing phone still work?

You can usually still use your current phone with Digital Voice, particularly if it’s a digital enhanced cordless telecommunications (DECT) phone, although it may need an adaptor. BT will provide one adaptor for free, but you’ll have to pay if you need more. 

When you have Digital Voice, your phone will be connected differently (via a router), but should work in much the same way otherwise. 

BT says that 99% of current phones will work with its Digital Voice service, but some older models may need to be replaced. If you need a new phone, you can order one at a discounted rate from BT rather than an adaptor. 

BT’s voicemail service (answer 1571) continues to work with Digital Voice. If you have your own answering machine, it should still work, assuming that your phone can still be used with Digital Voice via an adaptor.

Can I keep my existing phone number?

Yes. In the majority of cases you’ll be able to keep the same phone number when your service is migrated to Digital Voice. Exceptions can be if you change providers before you take a digital phone service, or if you change address – speak with your provider to discuss your specific circumstances.

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Do I have to pay to move onto Digital Voice?

No - you should never be charged simply to move to Digital Voice. Be aware that scammers have attempted to exploit the move to Digital Voice as an opportunity to extract money from people, or convince them they need to share personal information in order for their burglar alarm or healthcare device to continue working.

Be cautious if you’re called out of the blue, particularly if you’re given a tight timeframe and asked for bank details. Criminals may also create phishing emails or fake websites in order to try to get you to share personal data.

Scam phone calls can be reported by texting the word ‘call’ and the dodgy phone number to 7726.  Suspicious emails should be forwarded to report@phishing.gov.uk, and scam websites can be reported to the National Cyber Security Centre.

Do I have to have a digital phone line? 

No – you'll also be able to choose not to have a phone line at all. Providers offer 'broadband-only' deals so you can select a service that doesn't have a landline included. Use Which? Switch Broadband to compare the broadband deals on offer from the UK's major providers. We clearly state whether a phone service is included in each deal.

However, if you do want a landline phone service, it'll have to be a digital voice service from 2025. 

What if I don't have or want a broadband connection? 

Those who currently only have a landline won't be forced to pay for broadband services that they don't want or need. Their digital phone service will work using a special dedicated broadband connection and shouldn't cost any more than what they pay now. BT has made a specific commitment to telecoms regulator Ofcom that its customers will pay the same amount, and Virgin Media says its voice-only customers will get the hub necessary for its digital phone services at no additional cost. 


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Do digital voice services work if there's a power cut? 

A positive aspect of analogue phone services is that they continue to work in a power outage. That's not true of digital services. 

For many, a lack of a landline won't be too much of a concern, as 98% of British adults have a mobile phone. Mobile voice calls don't require 4G or 5G, and Ofcom says nearly all of the UK's properties get reception that's strong enough for indoor calls from at least one of the phone networks. If you call 999, it doesn't matter which provider you're signed up to, your mobile phone will connect to whichever network is available.

But those who don't have access to a mobile phone must not be left without a way to seek help in an emergency. Landline/broadband providers are responsible for additional protections to ensure customers can reach emergency services. 

BT is supplying vulnerable customers with a battery backup that will ensure digital phone services will work for an additional hour if any outage occurs and hybrid phones that can also work using mobile networks. Virgin Media's solution for those who need it is a device with its own battery that allows the landline phone to connect to mobile phone services. 

However, providing a battery backup or hybrid phone is just the first step - it's also essential that providers must ensure those who need one have help setting it up.

It's also worth keeping in mind that in power outages, DECT cordless phones won't work and mobile networks may also be affected. It's worth having a back-up plan with neighbours and family for peace of mind. BT has also told us it's working with power suppliers to help ensure that digital phone network resilience is prioritised if there’s a storm or other event that could cause outages.

I'm nervous about my phone service changing, what should I do?

The onus is generally on providers to identify customers who are reliant on their landline or are vulnerable. However, if you have concerns there are things you can do too, particularly if you rely on your landline or have a landline-dependent healthcare device.

A key step is to make your provider aware of your concerns before you’re migrated. All of the UK's providers have agreed not to force customers who have telecare devices to use digital phone services unless they are confident the customer will be left with a compatible and functional telecare solution in place.

Providers have solutions in place for those who don't have a mobile phone, or have poor reception. 

BT can supply hybrid landline phones to those who don’t own a mobile but live in an area with good mobile reception – these have both a built-in backup battery and Sim card. They use Digital Voice most of the time, but can switch over to a mobile network if there’s a power or broadband outage (the downside is they don’t have as many features as some other handsets).

If you don’t have reliable mobile signal, you should be offered a battery backup, but keep in mind that it will only support your router. Most cordless phones will also lose power in a power outage (because the base unit needs mains power), so you’ll need a corded phone you can use, if necessary. 

However, concerns about power cuts aren’t only about having access to emergency services – landlines have traditionally been our connection to others in tricky times. If you have neighbours or friends and family who are potentially vulnerable, it’s also worth considering alternative ways of checking in if there’s a power outage.

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What about other devices that use phone lines? 

Landlines aren't the only things that rely on the phone network. It also supports devices ranging from healthcare devices, burglar alarms, ATMs and card machines to traffic lights, motorway signs and railway signals. The copper phone network supports thousands of personal alarms and home monitoring systems that allow disabled people and those who are older or have health problems to access help if they need it. There are 1.7 million people using these telecare devices in the UK.

Effective digital solutions still need to be put in place for all of these before the copper network is switched off. Openreach told us that trials it has conducted in places like Salisbury and Mildenhall will help to ensure a smooth transition to digital services for the rest of the country.

Will my home burglar alarm still work with Digital Voice?

This depends on the system in your home and who it was provided by. Unfortunately, some security systems won’t be compatible with Digital Voice. 

Companies have been aware of the Digital Voice roll-out for some time, and many reputable brands have been exploring whether their services will still work using a digital phone service. The BT website has a list of firms that have tested the compatibility of their equipment with Digital Voice – it includes big names such as Chubb and Yale. But compatibility is still likely to depend on the specific system in question. 

Even if you’re still some way off migrating to Digital Voice, it’s worth contacting your burglar alarm provider to find out more about whether it will still work. Some will still work via your router and an adaptor, but others may require upgrading or replacement - and this can come at a cost. 

However, be cautious if you feel pressured to pay large sums to upgrade your system to work with Digital Voice - you should be given plenty of time to weigh up potential options.

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Will telecare devices still work with digital phone lines?

In some cases, yes. The industry has been planning for the switchover. Taking Care, the UK's largest private provider of personal alarms, told us the success of the digital switchover depends on telecare providers testing that their devices are compatible with digital services and working with customers to ensure they're set up correctly. Tunstall, a major telecare developer, has audited its equipment and planned a strategy to identify devices that won't continue to work.

BT and Openreach have also been working with the providers of telecare devices, allowing them to test in a special lab whether they work with digital phone services. 

Some existing devices will continue to work using a digital phone services, but others will need to be replaced. This could be an opportunity for an upgrade - the telecare industry has also been working to develop new products that work using digital phone lines or using a Sim card instead. Newer devices are likely to be more sophisticated and some also have their own battery back-ups so you don't need to worry about a power failure.

What should I do about my telecare device? 

Be reassured that you will not be asked to move to a digital phone service until your landline provider and telecare company are confident you will have a compatible and functional telecare device.

If you or a relative are concerned about the impact of the move to digital phone lines on your telecare device, it's worth contacting its provider – usually either a local authority or a private provider – to check whether the device will still work with a digital landline. Larger providers are likely to know which devices won't work using digital phone services and have been planning around this. Tunstall told us that many of the devices in use today have been specifically designed to work using both analogue and digital systems.

You might also want to let your telecoms provider know you have a device dependent on the landline – they will defer migrating you to digital services to allow for time to confirm that the device will continue to work. Ofcom has also made it a requirement for telecoms providers to identify people who are reliant on their landline and provide them with a free back-up option in case there's a power outage. 

Read more about telecare devices and how they can be used in the home.

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