The short answer
For almost every Australian small business in 2026, VoIP (Voice over IP) is the right choice. It's cheaper, dramatically more flexible, and the traditional alternative is largely being switched off underneath you anyway. The honest caveats: VoIP is only as good as the internet connection it runs on, and a sloppy setup gives VoIP its undeserved reputation for choppy calls. Get the connection and configuration right and there is no contest.
What changed: the NBN and the end of ISDN
Two structural shifts ended the landline era in Australia. First, the NBN rollout progressively disconnected the old copper network. In NBN fixed-line areas, traditional phone services were migrated or switched off, so many "landlines" today are already internet-based whether their owners know it or not. Second, Telstra retired the ISDN network that powered traditional multi-line business phone systems: new sales ended in 2018 and the network was wound down in the years after. The business phone systems of the 1990s and 2000s aren't being deprecated; they're already gone.
The practical question for a small business is therefore not really "VoIP or landline". It's "which VoIP setup, and is our internet ready for it".
Cost comparison
| Traditional lines (legacy) | Business VoIP | |
|---|---|---|
| Typical monthly cost | $40–$60+ per line, plus call charges | Roughly $25–$45 per user, calls typically included |
| Hardware | On-premises PBX hardware: thousands up front, plus maintenance | Cloud-hosted PBX: no phone-system hardware required; handsets optional (apps can replace them) |
| Adding a line/user | Technician visit, possible new cabling, weeks | A few clicks, minutes |
| National & mobile calls | Metered or bundled at extra cost | Usually included in the per-user fee |
These are typical Australian market ranges as at 2026. Plans vary, so treat them as a sanity check for quotes rather than a price list. For a five-person office, the total swing is commonly thousands of dollars a year, before counting the avoided PBX maintenance.
Call quality, reliability and what VoIP actually needs
VoIP carries calls over your internet connection, so the connection is the system. The requirements are modest, around 100 kbps per concurrent call, but the connection needs to be stable, not just fast. Three things separate crystal-clear VoIP from the choppy horror stories:
- A business-grade NBN plan appropriate to your team size;
- A router with QoS (quality of service) configured to prioritise voice traffic over someone's lunchtime video streaming;
- A failover path, typically a 4G/5G backup or automatic redirect to mobiles, for the day the internet does go down.
Features landlines never had
Cost gets businesses interested in VoIP; features are why nobody goes back:
- Your number follows you: answer the office line on your mobile, laptop or home office with the business number showing.
- Voicemail-to-email: missed-call recordings land in your inbox as audio files.
- Call routing and auto-attendant: "press 1 for sales" menus, business-hours rules, and queues that used to require enterprise hardware.
- Instant scale: seasonal staff on the Gold Coast in December? Add ten users for the summer, remove them in February.
- Integration: click-to-dial from your CRM, call logs against customer records, Teams integration.
When a traditional-style line still makes sense
Honesty requires the short list of exceptions:
- Lift phones, fire alarms and some medical/security alarms often have specific carriage requirements. These need purpose-built solutions, not a standard VoIP line.
- Locations with genuinely poor connectivity: where neither fixed-line NBN nor solid 4G/5G is available, voice over those networks inherits the problem.
- EFTPOS and fax devices on legacy dial-up connections need upgrading or special handling before the line they use disappears.
How to switch without losing your number
- Audit what you have: every number, line and device (don't forget the fax, alarm and EFTPOS lines nobody thinks about).
- Check your internet: plan, router and failover, per the section above.
- Choose the system and port your numbers. Porting is standard and regulated; your number moves with you.
- Run in parallel briefly. Keep the old service alive until the port completes and you've tested inbound, outbound and after-hours routing.
- Then cancel the old service, never the other way around.
This is one of our core services. BigByte Tech designs and manages VoIP phone systems for small businesses across Brisbane and the Gold Coast, including the internet, router and failover side that makes call quality bulletproof. Ask us for a phone system health check.