All you Need to Know about the PSTN Switch Off

The Public Switched Telephone Network (PSTN) is a legacy analog phone system that’s been around for a long time. Indeed, this technology has been serving the nation since the 1800s, so when the news came that Openreach would permanently switch off the PSTN network, it came as a shock to many. 

This article looks at everything that is crucial to this change, including why the phone system is being shelved, what’s replacing it, when the switch off will happen, what impact it might have on your business and how United Telecoms can help you throughout this migration.

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What is the PSTN switch off?

The PSTN switch off refers to Openreach’s decision to completely retire this old platform, which relies on underground copper lines and analog phone hardware to work. 

This means that all devices that rely on PSTN to function, most notably older landline phones, will no longer work after the switch off.

Why is PSTN being switched off?

Despite providing generations with reliable service, PSTN is being switched off as it is simply too old to keep up with modern demands. It can no longer manage the pace that communication needs to move at, and it also struggles to match the data-transfer capabilities of newer telephony technologies. 

This initiative is mainly driven by telecom operators who no longer want to partake in the expensive maintenance of a system that is growing more obsolete by the day.

PSTN will be replaced by VoIP (Voice over Internet Protocol). This technology allows phone calls to be made via a broadband Internet connection instead of a physical phone line that runs underground. The result is a more reliable, faster and cheaper telephone service. 

VoIP also doesn’t require the same local infrastructure as PSTN, and this provides the opportunity to implement systems that are flexible and scalable to suit your business needs. 

When is the PSTN switch off happening?

The big PSTN switch off is expected to happen at the end of December 2025. At the moment, there don’t seem to be any plans to perform a gentle phase-out or assist the public at large. There will also be a forced migration planned from April to December 2025.

So, if your business still has devices and systems that are reliant on PSTN, it’s best to make arrangements to switch over to VoIP before then, and here at United Telecoms, we can help you with this transition.

Who will be impacted by the PSTN switch off?

This change will affect all businesses that currently still use PSTN and ISDN services. Individuals who rely on the same systems but in their homes for private use will also be impacted by the switch off. 

How will the PSTN switch off affect my business?

At first glance, the switch off might not seem so bad. After all, it just affects phones right? Well, not quite. The day PSTN finally retires, it could affect other legacy technologies that are linked to the network. This could cause a small disaster for any business that needs such devices on a daily basis.    

Some examples include telecare devices, fax machines, security systems, fire alarms and retail payment terminals. Most of the older models are designed to work with PSTN features that cannot be entirely duplicated in VoIP platforms. For this reason, you might have to upgrade such devices and systems to make sure that they stay functional after the switch off. 

If such upgrades and a successful switch to VoIP phones are not made in time, your business could face the loss of several foundational elements. These include your communication network, record systems, payment devices that allow clients to pay on-site, and even safety systems. 

Another network that will also be affected is the Integrated Service Digital Network (ISDN). This was basically the first version of high-speed Internet that was launched quite a few years ago in the 1990s. While it set the scene for better, faster Internet solutions, ISDN is now also being replaced for the same reasons as PSTN. 

After 2025, no one will be able to purchase either PSTN or ISDN in the UK.

What is replacing PSTN?

Although some discussion still seems to be in the works, it’s almost universally agreed upon that VoIP is the chosen technology that will eventually replace all PSTN and ISDN networks. 

The main attractions of VoIP include faster communication and data transfers, features that support business growth, no unsightly phone lines snaking about in the office or at home, cheaper rates and better call quality. That’s just scratching the surface of how Internet-based telephony technologies can benefit companies and individuals alike. 

Another aspect that you need to be aware of, since it’s likely to become a major player after the switch, is Session Initiation Protocol (SIP). SIP trunking is a service made available to users by service providers. It can be useful if you don’t want to get rid of all the phones in your office. How so? SIP trunks allow you to use VoIP connectivity to link your existing phone system to the public phone network via the Internet. 

How do I prepare my business for the PSTN switch off?

While a good telecom company can assist you in seamlessly transitioning to a new system like VoIP, there are things that you can do beforehand to ensure your business is prepared for the PSTN switch off. 

  • Assess Your PSTN Systems and Devices

When the switch off occurs, everything that runs off your PSTN phone lines will shut down. As mentioned a little earlier, it’s essential to know which devices and systems in your business still rely on this traditional network to function.

Keep in mind that some might not be so obvious. Take the time to look at all your technologies to flush out any PSTN-dependent items, but in particular, examine your payment terminals, cash machines, panic alarm system, fax machines, lift emergency lines and even door entry systems. These are the ones that commonly work with PSTN. 

Once you have an idea of the PSTN landscape in your office, it might be helpful to draw up a complete list of such devices and systems to show your chosen provider. The latter can then assist with the necessary updates to keep them functional.

  • Check the Strength of Your Internet Connection

To future-proof your connectivity against the switch off, your Internet connection needs to be strong enough to handle VoIP capabilities. Weak or unreliable broadband connections simply won’t do and can cause issues like poor-quality calls, dropped calls, or a system that doesn’t function.

It’s best to upgrade to a provider package that offers both high bandwidth and low latency. This way, you can enjoy the best of your new network, including quality audio, no lost calls and HD video conferencing.

  • Learn More About Softphones and Software

Once PSTN disappears, so will a significant number of traditional telephony hardware. There won’t be any need for cables, large servers, or bulky handsets, just to name a few. 

The advantages are clear; your office will be more spacious and neat, most maintenance issues will disappear, and it’s also safer not to have electrical wires everywhere. 

However, you still have to understand and operate the things that will replace your old hardware. In this case, softphones and software programs. The good news is that all VoIP-related technologies are normally not hard to master. Many people claim that the learning curve is manageable and intuitive.

When you brush up on your VoIP technology, there is an added benefit. The variety of the different provider packages can be confusing. They offer so many different handsets and features it’s enough to make any beginner’s head spin; but, once you know more about the terminologies and capabilities of VoIP systems, then you can confidently choose a package with the best phone features for your business.

  • Train Your Employees

This is a stressful time for staff too. They must complete projects, call clients, close deals, get information and make sales. They might be nervous that a whole new telephone system might interfere with their ability to do their work. 

As an owner, you don’t want hiccups in the workflow, either. Both workforce stress and interruptions can be negated by timely training. It might be best to provide your staff with information about VoIP, even as they continue to use the old PSTN system for the final few months.

At the end of the day, perhaps the most important step you can take to prepare for the PSTN switch off is to act now. This will give you sufficient space to deal with unexpected curveballs and training and to switch over to a new VoIP system in your own time. 

Advantages and disadvantages of the PSTN switch off

The only real disadvantage of the PSTN switch off is inconvenience. Many business owners have been using PSTN for years and are happy to continue using it. It might also annoy some people that they weren’t given a choice in the matter. 

However, once you recognize the top benefits of VoIP as a telecoms system, it can make the coming switch off, as well as the related effort and expenses, worth the trouble. 

Here are just some of the key advantages that you can expect:

  • Easy to set up
  • More flexibility than legacy systems
  • Ability to collaborate on different devices
  • Supports a remote workforce
  • Affordability; pay a flat monthly rate
  • Scalability; easily add or remove lines as you need them
  • Prevents system failures and outages
  • Improved customer experience
  • Phone analytics
  • Increased productivity
  • Better system security and backup
  • Effortless to maintain and update

How can United Telecoms help my business with the PSTN switch off?

United Telecoms has decades of experience with internet and telecommunication solutions. Our experts can assess your company’s current situation and devices for the best recommendations. You can also contact us to find out more about how United Telecom can help your business make a successful transition to VoIP from PSTN.

FAQs about the PSTN Switch Off

What is the difference between PSTN and VoIP?

PSTN is an old phone system that was invented in the 1800s and relies on underground copper wires to work. VoIP is a younger technology that became available in 1995. 

Instead of relying on old-fashioned infrastructure, a VoIP telephone system uses the Internet to make and receive calls.

What is the difference between PSTN and ISDN?

ISDN works with digital signals and can transmit both voice and data over a digital line. Similar to PSTN, it can work with copper-based lines, but there are several differences between the two. 

ISDN is the newer technology and can run two connections simultaneously (like a phone and fax), but PSTN is limited to only one at a time. ISDN is also more versatile and offers extra features such as call forwarding, caller ID, call waiting and three-way calling. 

Can I keep my current phone number in the PSTN switch off?

Yes; when the switch off happens, and everything moves over to VoIP, you can keep all your existing numbers. United Telecoms will take care of the number porting for you.  

Will IP be better than PSTN?

Yes, IP will definitely serve users better than PSTN. You can look forward to wonderful perks like massive cost savings and maintenance responsibilities that mainly fall on your new hosting provider. IP is also more future-proof and will better adapt to technological changes in the coming decades. 

One of the best advantages is the wide variety of IP phone features. They are specifically designed to boost productivity and collaboration, something that’s more difficult to accomplish with PSTN networks.

Got questions? Contact our experts today.


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