Sip Trunks

Keep your onsite PBX ringing with Prosum's SIP Trunks

Prosum’s SIP service is a smart and cost-effective way to connect your existing PBX phone system to the PSTN. SIP Trunks are IP-based connections allowing you to make calls from your existing phone system. They are highly scalable and will seamlessly grow alongside your business. So as your business expands and higher call volumes are required, you can quickly and easily add more lines and users.

sip trunk benefits

 Cost Savings

Your business benefits from an affordable connection, reducing line rental fees and call charges.

Highly Scalable

Welcoming new staff or expanding to another site? Make changes quickly & easily when & where needed.

High-Quality Calls

Your private, dedicated bandwidth with QoS ensures your voice calls are always heard crystal clear.

Keep your calls flowing

Unplanned disruptions? Redirect your calls to your chosen recovery site or mobile number of your choice.


24/7 Support Desk

Our 24/7 support teams are based across Australia and available around the clock.

*Keeps Your Current PBX

No need for costly hardware updates. Our SIP Trunks ensure broad compatibility.



*Prosum’s SIP service provides a high-quality SIP Trunk over the internet or a dedicated connection connecting to an IP-based or a legacy ISDN phone system. Our SIP trunking service is suitable for small to large organisations looking for high quality, cost-effective, scalable telephony access. Not sure if your PBX phone system will work with our SIP Trunk service? Please get in touch with our team; we’re happy to check for you.

Why Prosum as your Business Communications provider?

Trusted Technology Partners

We’ve partnered with the best Australian tier 1 carriers including Vocus & Access4.

Highly Reliable Communications

Run your business successfully with 99.99% maximum uptime on all voice applications

25+ Years Going Strong

We’re your single point of contact to a diverse range of in-house skilled & certified technicians.

Award-Winning Support

You’re always backed by our 24/7 support team based here in Australia & available around the clock.

  • Aitken Real Estate had to move office and sought Prosum's advice about switching our telephony to the cloud. Extremely helpful, no-nonsense information and can get the job done. Their tech Antoine was sensational. No delays, no problems. Highly recommend!


Contact Prosum to find out how we can help you save on communication costs and extend the life of your onsite PBX with our SIP Trunking solution.

1800 007 229