SIP Trunking

C2 Communications’ SIP Trunks Are Tier 1

C2 Communications’ SIP Trunks are provisioned on Tier 1 carriage to provide fast provisioning of new services, excellent quality of service, and direct routing to the Australian telcommunications network.

Our efficient VoIP services ensure your telephony bill from a traditional fixed line carrier will reduce by up to 50% on call costs and line rental.

3CX  Supported VoIP Provider

C2 Communications’ SIP Trunks were the first 3CX supported SIP services in Australia over 10 years ago. The strength of our VoIP services have been maintained ever since, with a strong record in excellent service delivery and commitment to both platforms. Our efforts have continued to be recognised in recent years, with our unbroken run of consecutive years as a 3CX Titanium Partner making us one of Australia’s most preferred VoIP providers.

Pricing Guide

Our full rate card available here.


SIP Line $10 per month

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National Calls $0.10 per call

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Local Calls $0.10 per call

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Mobile Calls $0.22 per minute (billed per second, no flagfall)

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Unlimited SIP Pricing

After an unlimited SIP line? C2 Communications also offer unlimited SIP for customers who solely require a voice solution.

Unlimited SIP line $39 per line Includes all local, national and mobile calls

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How it Works

C2 Communications SIP Trunks are provisioned on request on our Tier 1 carriage softswitch. Our SIP Trunks register onto our network using 3-way authentication from your 3CX Phone System. As a preferred VoIP Partner, C2 Comms authentication templates can be found in the VoIP registration field of the PBX. To see how to authenticate a C2 Comms SIP Trunk in further detail, follow our guide.

Our Customers

Benefit from a strong relationship with a service provider that delivers.

What Our Clients Say

  • Fantastic support and staff, they truly understand what it means to be a business partner.


  • We’ve had these guys looking after our phone and I.T. needs at work since 2010 and they’ve always been fantastic. Service is always spot on and they’ve never let us down. I won’t even speak to any other company trying to poach our business.


  • The technical and professional staff at C2 Communications have been extremely helpful in getting our entire IT&T networks to work smoothly and effectively across several Melbourne offices. With the high volume of telephone calls made, we have certainly benefited economically with the decision to install 3CX. The IT team has been highly responsive and we would not hesitate in recommending both their IT services and VoIP solutions.


  • C2 Communications installed our 3CX phone system and it works seamlessly between our several sites. The changeover to using SIP lines has proven to be extremely cost effective. After the installation, our staff were trained on how to manage the system internally and we are particularly impressed with its reliability and functionality. It’s definitely been a positive move for our business.