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SIP (Session Initiation Protocol) trunking is a solution which enables voice and video calls over the internet.  SIP trunks are carried over IP network instead of a traditional phone line, helping to reduce your call rates. 
ISDN will be switched off in 2025
Over 1 million  Businesses use ISDN currently
Up to 25% Save on call costs with SIP

Are you ready for the ISDN switch off? 

BT has announced it will switch off its Integrated Services Digital Network (ISDN) by 2025, starting the process in 2020. ISDN is used by over one million UK businesses so unless you’re using a cloud-based solution such as VoIP or SIP it’s likely you are operating via ISDN.  

SIP Trunks are one of the cheaper hosted alternatives to ISDN and offer business continuity to ensure you never miss a call.  

Choosing Sip Trunk helps to reduce your costs thanks to the lower call costs, the free internal calls and lower line rentals. Plus, diverting business calls is easy allowing you to work from anywhere.  

Benefits of SIP Trunking

Future-proofed solution
Lower costs
Business continuity
Work from anywhere

Introducing SIP Trunk Call Manager

The ideal add-on to your existing SIP trunk

SIP Trunk Call Manager is a comprehensive inbound call handling tool for businesses that put customer service at the heart of their organisation. You can easily control and manage your inbound numbers via a single online account, accessible via a web portal and a mobile app. Perfect for when you are on the move, outside the office and working from home. You can redirect calls or invoke business continuity plans in case of an emergency from the palm of your hand. Plus, additional bolt-on’s to further enhance the service are also available.

Enhanced SIP Service

Gives you full control of your inbound numbers, easily and securely managed by a single account.

Never Miss a Call

Designated Business Continuity call plans that can be instantaneously invoked from the app.

App and Web Portal

One point of contact providing your SIP trunks and call management via one simple solution.

SIP Trunk Call Manager App

SIP Trunk Call Manager App

The SIP Trunk Call Manager app offers users an additional way to access inbound routing functionality. 

From the app, users can view their company’s account list of DDI numbers. It also has a separate section dedicated to Business Continuity which enables to filter numbers that have an active or inactive validated DR call plan.

How We Work With You


Our team of experts will assess your environment and advise on the implementation of best voice solutions – connect your people from anywhere and any time 


Our engineers boast the latest accreditations from leading bodies and will deliver the solution and help you rollout enhanced features. 


We can provide you with training and materials to ensure your people adopt fully the new technology and help them to work better together. 


You can also choose our expert team to provide continuous support throughout your journey, helping you to stay connected at all times. A variety of managed support options available.  

Useful Resources


BT ISDN Switch Off - Are You Ready?


Everything You Need to Know About the ISDN Switch Off


6 Reasons Why You Should Switch to Cloud Telephony

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