SIP Lines

Connect your phone system with PROSUM'S NBN ready SIP lines and save.

SIP Lines With our SIP Lines, you’ll experience great savings and get advanced features when you connect your VoIP phone system.

SIP Lines* replace traditional PSTN/ISDN line rental fees and call charges, therefore providing you with free inter-office calls and very low call rates via your internet connection.

Prosum’s Sip Lines at a glance

  • Quick & easy to setup
  • NBN ready
  • Compatible with most PBX’s
  • Scalable
  • Cost Effective

*SIP Lines are the equivalent of traditional PSTN/ISDN lines.

How SIP lines can benefit your business

Reduced costs

You’ll get instant savings on call costs and line rental when you switch, plus free inter-office calls, per second billing and very low local, national and international calls.


Switch easily

Want to keep your existing business phone numbers? You can transfer your phone numbers** easily to PROSUM and we integrate with all major ISDN and IP PBXs***.

Easily scalable

You can increase or decrease the number of lines quickly, and in much less time than traditional ISDN services, and even expand to other office locations without having to buy a new PBX.

Maintain business continuity

If your site is down due to unplanned disruption, you can keep your calls flowing by redirecting them to your chosen recovery site or to a mobile number of your choice.


If your considering Unified Communications features into your business, SIP lines are a simple and cost-effective way to prepare your network for these technologies, making them easier to deploy.

We support you

By choosing PROSUM SIP lines, you receive national network coverage backed by experienced 24/7 support teams across Australia.

**Number porting is dependent upon the incumbent carrier releasing your numbers.
***Contact us to confirm the compatibility of your PBX brand & model.

What our clients say about us

  • Professionalism at its highest standard. Over the many years of association our firm has utilised and highly recommend a variety of PROSUM'S services including data and telephone. More recently our firm relied on their advice and direction when installing and upgrading our telephone system. We continue to use these services with great leadership by David Colletta and a great team.


Ready to make the switch?