Business Phone System Australia: What to Buy

Types of Business Phone Systems Available in Australia

Hosted PBX: The Standard Choice for Australian SMBs

A hosted PBX (cloud PBX) is the most practical business phone system for the majority of Australian small and medium businesses. The call switching hardware runs in a provider's data centre; you pay a monthly per-seat fee and plug in SIP desk phones or use a softphone application. No on-site hardware beyond the phones is required. Hosted PBX services in Australia typically include: auto attendant (press 1 for sales), ring groups (ring multiple phones simultaneously), voicemail to email, call recording, call queuing, and support for 1300/1800 inbound numbers. For most businesses, the feature set of a hosted PBX exceeds what they actually need. See our VoIP phone system guide for specific provider comparisons.

What About Microsoft Teams Phone?

Microsoft Teams Phone (formerly Teams Calling) is worth serious consideration for businesses that are already embedded in the Microsoft 365 ecosystem. It integrates phone calls directly into the Teams application - the same interface used for internal messaging and video calls. This eliminates the need for separate SIP phones for many users (calls can be handled on a headset or through the Teams desktop app).The limitations are: it requires a Microsoft 365 subscription, call quality is dependent on Microsoft's network routing which can be less predictable than a dedicated VoIP provider, and complex call routing scenarios (multi-site ring groups, sophisticated IVR) require additional configuration expertise. For a business that already pays for Microsoft 365 and values simplicity over telephony features, Teams Phone is a compelling option.

What to Look for in an Australian Business Phone System

When evaluating any business phone system for an Australian deployment, these criteria matter most:Australian number support: can the system provision and manage Australian geographic numbers, 1300, and 1800 numbers? Number porting: can the provider port your existing numbers from Australian carriers including Telstra and Optus? NBN compatibility: has the provider tested their system on Australian NBN connection types including FTTN? Local support: is there an Australian support team available during business hours? Contract flexibility: are you locked into a minimum term, and what are the exit conditions?

The NBN Factor

All modern Australian business phone systems route calls over the NBN or other internet connections. The PSTN copper network is being decommissioned progressively as NBN connectivity reaches each area. This means the quality of your NBN connection directly affects the quality of your phone system, regardless of which provider you choose.For detailed guidance on optimising your NBN connection for voice, see our NBN VoIP setup guide. If you are on an FTTN connection and experiencing quality issues, our call quality guide covers the specific diagnostics.

What to Avoid

Avoid new installs of legacy analogue PABX hardware. In NBN-served areas (which covers most Australian businesses), analogue PABX systems require an ATA (Analogue Telephone Adapter) to connect to a VoIP service, introducing an additional failure point. Existing PABX hardware can often be retained temporarily using an ATA, but replacing it with a hosted PBX or IP-PBX system gives you a more maintainable long-term solution.Avoid providers with long lock-in contracts for hosted PBX services. Cloud PBX is a competitive market; month-to-month or short-term contracts protect you if the service quality does not meet expectations. Avoid providers who cannot demonstrate local Australian number porting capability before you sign up - number porting failures are one of the most common sources of business disruption during a phone system migration.

What is the difference between a PBX, a PABX, and a hosted PBX?

PBX (Private Branch Exchange) is the generic term for any phone switch that connects internal extensions to external phone lines. PABX (Private Automatic Branch Exchange) is the traditional term for the analogue hardware box that was standard in Australian offices for decades. Hosted PBX is a cloud-based version where the switching hardware runs at a provider's data centre rather than in your office. For Australian businesses today, hosted PBX has largely replaced traditional PABX hardware.

How many phone lines does a small business need?

For a hosted VoIP system, you do not need to pre-allocate a fixed number of lines. Hosted PBX services support multiple simultaneous calls on a single account based on the number of active seats. A business with 10 staff members who make occasional calls might need 3-5 simultaneous call capacity; a business with 10 staff who frequently make outbound calls simultaneously might need closer to 10. Your provider can advise based on your usage patterns.

Can I use my existing office phones with a new VoIP system?

If your existing phones are SIP-compatible (most IP phones manufactured after 2010 are), they can potentially be reprogrammed for a new hosted PBX provider. However, provisioning compatibility varies between providers and phone models. Old analogue phones require an ATA (Analogue Telephone Adapter) to connect to a VoIP system. In most cases, the simplest approach is to use the phones your new VoIP provider supports and pre-configures.

Does my business need a dedicated internet connection for phones?

No. Modern hosted VoIP systems share your existing internet connection with other business traffic. Properly configured QoS (Quality of Service) settings on your router ensure voice traffic is prioritised. For most businesses with standard NBN connections, the existing internet service is more than adequate. Separate voice-dedicated connections are only necessary for very high call volume businesses or those with consistently poor internet quality.