The Big Switch Off

The Big Switch Off

The 2025 Big Switch Off is nearly upon us. Whilst it still seems a while away, businesses should start planning their migration now as 2025 isn’t the start, it’s the completion date. The work has already begun!

In this blog we’ll explain what The 2025 Big Switch Off is, what it means and what you’ll have to do.

What is the Big Switch off?

First announced by Openreach in 2015, the Big Switch Off means the end of both the PSTN – or the Public Switched Telephone Network – and the ISDN – the Integrated Services Digital Network.

PSTN, or what we all know as the landline telephone system, has been around since 1875. The system uses traditional copper wires and telephone exchanges and was built for analogue communication. In the 1960s, the system was enhanced to allow digital transmission of voice data across its network, creating ISDN.

Both of these systems are to be permanently switched off in 2025 and the winding down has already begun.

What will I have to do?

The Big Switch Off means that if you haven’t already done so you will have to begin using an internet enabled solution – IP Telephony. When moving, there are a couple of options: SIP Trunking or a Hosted Phone System. Both of these enable you to make calls over the internet, but differ slightly in set up and how they work.

Session Initiation Protocol (SIP) trunking allows you to make calls through your on-site internet connection via your on-site PBX. When making an outbound call, calls are routed from your PBX through your SIP Trunk over your internet connection. When receiving an inbound call these come via your SIP Trunk through the PBX to your phone.

A Hosted Phone System or Hosted PBX is a completely Cloud-based solution. This is the perfect flexible solution for where remote working is required. Calls are made over VoIP (Voice over Internet Protocol) meaning all you need is an internet connection and you can call from anywhere, on any internet enabled device – Laptop, desktop, mobile or tablet.


Switching is very simple, but you should consider the following before making a change.

Do you have an on-site PBX?

If “yes”, you may prefer to keep your existing equipment and adapt it to make it suitable for after the switch off. If you’re considering this option, it’s important that your PBX supports IP telephony, otherwise you’ll likely be presented with huge upfront costs for a new IP compatible PBX.

If “no”, then make the switch to a fully hosted solution. It’s low cost, easy to manage and is easy to scale so can adapt to your business growth.

Number Porting

Plan your number porting – particularly if you want to use existing numbers or location-specific numbers. This can take a few weeks depending on how many numbers need porting, so it’s important you mention this to the provider to avoid business disruption.


As we move towards a hybrid working model, or in some cases full remote working, it’s important to think about how your solutions can support this long term. The ability to easily transfer between locations and work seamlessly from wherever you are is key for many businesses. A hosted phone system is the ideal choice for this – it provides the flexibility and agility needed for staff to use the phone as normal wherever they are based.


In our opinion, there really are only two products worth considering: TeamsLink from Wavenet and Microsoft’s own Phone System. It’s important to remember that these are the only two products that are native to Teams. The biggest difference is that Wavenet have inhouse developers that work to enhance Teams further. The additional features and functionality that TeamsLink has make it the best product on the market – and as a long-standing Microsoft Gold Partner, we don’t say that lightly! Here are the main differences:

Simple Pricing and Inclusive Minutes

Whilst Microsoft have calling plans, like a mobile phone contract this can be expensive if you go beyond your assigned minutes. Wavenet however have a different costing model and their plans contain unlimited UK and International calls across 90 countries meaning there’s just one simple, low monthly cost.

Simple Set up and Management

In terms of set up and management, Wavenet is considerably easier than Phone System as it uses an intuitive and user-friendly visual portal. With simple drag and drop functionality, you can set up and manage call routing, automated call attendant, and ring and hunt groups.

Voice Recording

Whilst Microsoft Phone System has call recording, TeamsLink take things further by offering FCA and MiFID II Compliance Recording.

With a whole raft of additional features such as Advanced Power BI reporting, Skill Based Routing and Disaster Recovery, TeamsLink offers benefits and features beyond Microsoft Phone System. If you’d like to talk about the above or if you’d like to know more about TeamsLink give us a call on 01492 862780.