Hosted PBX vs VoIP vs SIP Trunking: the short answer. For Australian businesses evaluating their options, understanding these three terms is the first step. VoIP is the underlying technology that carries voice calls over the internet. A hosted PBX is a complete, managed business phone system built on top of VoIP – it adds call routing, extensions, IVR menus and admin tools, and is run for you in the cloud. SIP trunking is a connectivity service that replaces traditional phone lines, letting an on-premise PBX send and receive calls via the internet instead of the old copper network.
What Is VoIP?
VoIP (Voice over Internet Protocol) is the method of sending voice calls as data packets across an IP network rather than through traditional analogue lines. It is the foundation that all modern business phone technologies are built on, including hosted PBX systems and SIP trunks. By itself, VoIP is a protocol, not a product. You need a service or system built on top of it to make and receive business calls.
What Is a Hosted PBX?
A hosted PBX (Private Branch Exchange) is a fully managed business phone system delivered from the cloud. The telephone exchange – the hardware and software that routes calls between extensions, handles IVR menus, records voicemail and generates reports – lives at your provider’s data centre, not at your premises. You access it through desk phones, mobile apps and browser extensions. Because there is no on-site hardware to maintain, a virtual phone system like this suits businesses of any size, from sole traders through to multi-site teams.
Smart Phone Systems delivers hosted PBX solution. You can explore the full features list or see how our VoIP phone system works end to end.
What Is SIP Trunking?
SIP trunking is a service that connects an existing on-premise PBX to the public telephone network via the internet, replacing old ISDN or PSTN lines. SIP (Session Initiation Protocol) is the signalling standard that establishes, manages and ends VoIP calls. A “trunk” is simply a bundle of simultaneous call channels. Businesses that have already invested in an on-premise phone system often adopt SIP trunking to cut line rental costs rather than replacing the whole system.
Hosted PBX vs VoIP vs SIP Trunking: Side-by-Side Comparison
| Feature | VoIP (Protocol) | Hosted PBX | SIP Trunking |
|---|---|---|---|
| What it is | Internet voice technology | Managed cloud phone system | Internet phone lines for existing PBX |
| Hardware required | Depends on the product | None on-site | Existing on-premise PBX |
| Who manages it | You (or your provider) | Your provider | Split — your PBX, provider’s lines |
| Setup complexity | Varies | Low — provider handles everything | Medium — requires PBX configuration |
| Scalability | Varies | Very easy — add users in minutes | Easy to add channels |
| Cost model | Varies | Monthly per-user fee | Monthly per-channel/per-minute |
| Best for | Any modern phone solution | SMEs wanting a complete solution | Businesses with existing PBX hardware |
| Australian NBN/fibre ready | Yes | Yes | Yes |
Which Business Phone System Is Right for Your Australian Business?
For most Australian small and medium businesses, a hosted PBX is the practical choice. There is no capital outlay on hardware, no in-house IT skills required, and the system grows with your team. Call routing, IVR, voicemail to email, mobile apps and reporting come included and not as expensive add-ons.
SIP trunking makes sense if you have already invested in an on-premise PBX and want to replace expensive ISDN lines without ripping out the whole system. It reduces line costs but leaves you responsible for maintaining the physical hardware.
VoIP as a standalone term is not really a purchasing decision, it is the technology underpinning both hosted PBX and SIP trunking. When someone asks “should we go VoIP?”, they are really asking whether to move away from old analogue or ISDN lines. The answer for Australian businesses is almost always yes, particularly now that the NBN rollout has made reliable internet connectivity the norm.
Why Hosted PBX Wins for Most SMEs
- No hardware to buy or maintain. These systems run in the cloud
- Works on any device. You can choose from a range of desk phones, portable phones, mobiles and browser extensions, or mix and match for a solution that works for you.
- Professional features from day one. IVR menus, call queues, voicemail to email.
- Australian-based support. Setup and ongoing help from a local team
- Scales with your team. We can add or remove users when you require it.
Ready to Make the Switch?
Smart Phone Systems provides hosted PBX for Australian businesses across Melbourne South East and Gippsland, and supports businesses nationally. We handle design, setup, number porting and ongoing support so your team can focus on answering calls, not managing technology. See all features or learn about our virtual phone system.
