What is SIP Trunking?

A SIP Trunk is the digital equivalent of a phone line and requires an existing phone system which cannot be setup without a technician.  Replacing a traditional phone line, A SIP Trunk enables you to make and receive voice (or video) calls using the internet and is perfect for small offices to large enterprises.

Why use SIP Trunks?

SIP Trunking will reduce business costs, prepare your communications for NBN and may improve the quality of your phone service.


SIP Trunks will be the global standard for voice communications in the NBN era as it’s a cost effective and flexible system that supports fast growth around multiple geographic locations.

Cost Effective

Instead of using traditional analogue PBX, SIP Trunks can save your customers up to 50% off their monthly bill in most cases. All due to call rates being lower and the elimination of landline rental fees.

Team Management

With easy access to our admin portals, your IT team will have the flexibility to adjust call routing, change extensions, add handsets and more on demand with no calling off shore call centres for help.

How SIP Trunking Works

SIP Trunking acts as a virtual connection between an organisation and an Internet Telephony Service Provider (ITSP) either via lines that link SIP trunks to other IP traffic, or through the Internet via a Virtual Private Network (VPN).

During a call, you can have any of the following scenarios and more:

  • Be on a voice call with one other person
  • Have multiple people on a conference call
  • Run video calls

See the diagram on the right showing how calls flow from a SIP phone (VoIP) in a business to the internet.

Nowadays, instead of routing voice calls over copper lines, SIP trunking sends them over data networks. In other words, the physical phone line is replaced with a virtual one which provide better quality voice solutions.

The setup you’ll need to make the switch to SIP trunking includes the following:

  • NBN Internet connection
  • SIP-compatible PBX (Private Branch Exchange) box, also called IP PBX
  • VoIP phone, or VoIP adapters if you’ll use your existing traditional phones
  • Network connection for your phones

If you have an older PBX system, you may need a SIP-ISDN gateway. Newer systems may not require this additional hardware.




Onsite PBX




NBN Network


Is SIP Trunking right for me?

SIP Trunking is just one of many ways to run an office phone system. It may not be a suitable solution for every business. Importantly, SIP Trunking requires an existing phone system and cannot be setup without a technician.

Can I keep my old phone system?

Our SIP Trunks are interoperable with all major analogue and IP phone systems. SIP Trunking can also provide the voice calling component in Unified Communications software – such as Skype for Business (Microsoft Lync).

Support Included?

If there’s ever a problem, we’re here to help. Business technical support is available via phone or email Monday – Friday, from 9.00am to 5pm (AET).

Our SIP packages offer flexibility and reliability to our partners and peace of mind that they are on the most reliable voice networks on offer to market.

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