SIP trunking

SIP trunking is a unified communication solution which delivers a brilliantly flexible and lower cost alternative to traditional ISDN lines for a business phone system.

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What is SIP trunking and how does it work?

SIP trunking stands for Session Initiation Protocol and is a telephony technology that enables businesses to make and manage voice calls, and other unified communications services over the internet. Essentially, SIP trunks are virtual phone lines that enable users to make and receive phone calls over the internet to anyone in the world. With the impending ‘Big Switch Off’ of the public switched telephone network (PTSN), SIP trunking is rapidly replacing traditional ISDN lines. It connects PBX to the PTSN via broadband, ethernet or private circuit into our national network. SIP trunks are a highly flexible alternate to ISDN and compatible with all the leading IP PBX brands in the UK market. Ultimately providing you with peace of mind that your PBX hardware works with the network service. SIP trunking technology is suitable for any business from small scale set-ups to enterprise organisations and - as a leading provider of SIP trunking solutions - Focus Group are ready to deliver the huge benefits of the ‘SIP switch’ to your business.

SIP trunking features

Why upgrade to SIP Trunking?

Compared to ISDN, the SIP trunking solutions delivered by Focus Group are less costly per channel. Your business could save up to 50% on telephone line rentals and 25% or more on call costs! It is also quicker to install and provision, delivers extremely robust business continuity plus provides more reliable and flexible connectivity.

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Sip Trunk Call Manager

SIP trunk call manager

SIP trunking manager allows for business continuity as standard, giving you the ability to manage all your numbers, regardless of geographical location, and all aspects of your inbound calls onto a single platform, meaning that you will never miss a call again.

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SIP trunk call recording

Our SIP trunking solutions allow you to record all calls coming into and out of the business. Meaning that you can use call recording to improve staff performance and increase customer satisfaction.

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Sip Trunking Call Recording

What are the benefits of SIP trunking?

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Scale up and down when you want

SIP trunking scales with your business. SIP trunks are perfect if you are looking to move premises, upsize, or downsize and want to keep using your current number. Scale up lines during busy periods and back down again afterwards. You can add lines, take them away, split calls at any time. You are always in control.

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Save money on call costs and line rental

SIP can deliver less costly, more reliable connectivity than ISDN over an IP connection. It can save up to 50% on phone line rentals and 25% or more on call costs.

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Compatible with Skype for Business

Our SIP trunks are integration tested and approved to interoperate with Microsoft Skype for business, allowing you to directly connect to the platform to make external calls.

SIP trunking packages and pricing



£5.99 Per month

  • ✔  2 - 50 channels
  • ✔  Unlimited DDI's
  • ✔  No minimum call charge
  • ✔  Competitive call rates
  • ✔  No connection free

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£19.99 Per month

  • ✔  8+ channels
  • ✔  Unlimited DDI's
  • ✔  No minimum call charge
  • ✔  Competitive call rates
  • ✔  No connection free

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Frequently asked questions

VoIP is Voice over Internet Protocol. It is a technology that allows a user to make phone calls through internet instead of a regular landline or a mobile network where as SIP connects on-premise PBX to the PTSN via broadband, ethernet or private circuit into our national network.

VoIP is a cost-effective, easy-to-implement, voice only solution. It can be enhanced with SIP, which offers more flexibility and a unified communication solution by offering multimedia communication in addition to voice.

PBX (Private Branch Exchange) is a system that connects individual desk extensions to telephone lines and mobile networks. SIP enabled PBX is a PBX that can connect to the internet and use SIP to make calls over the internet.

Business phone system case studies

Brewers Uk

Cisco SD-WAN simplifies retail branch networking for Brewers.

Somerset House Uk

Adopting a Cloud-First strategy, Focus delivers a true digital transformation for the 18th century.

Honda Uk

Europe's largest mesh wireless infrastructure. Honda gets connected with Focus.

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