The PSTN switch-off Australia is rolling out now, and businesses across the country need to act. Telstra is permanently retiring Australia’s copper telephone network, the one that has carried business calls for decades. If your business still relies on a traditional landline, ISDN service, or an older PBX phone system, this change directly affects you. This guide explains what is happening, what it means for your phones, and what you need to do before the deadline reaches your area.
What Is the PSTN and Why Is It Being Switched Off?
PSTN stands for Public Switched Telephone Network. It is the legacy copper wire infrastructure that Telstra built across Australia over many decades to deliver traditional landline phone calls. Alongside PSTN, many businesses also use ISDN. Integrated Services Digital Network, lines that carry multiple calls simultaneously over the same copper infrastructure.
Telstra announced the progressive decommissioning of its copper network as part of Australia’s broader transition to the National Broadband Network (NBN). The fundamental reason is straightforward: maintaining ageing copper infrastructure alongside a modern fibre, fixed wireless, and satellite network is not viable long-term. The copper network was never designed to last indefinitely, and the cost and complexity of maintaining two parallel networks grows every year.
The PSTN switch-off Australia is not a single event. Telstra has been progressively retiring copper services area by area since 2022, with the process continuing through 2025 and beyond. When the copper network is retired in your area, PSTN and ISDN services stop working permanently. The Australian Communications and Media Authority (ACMA) provides guidance on your rights during this transition.
Which Services Are Being Discontinued?
Telstra is retiring the following services as part of the copper switch-off:
PSTN analogue lines: Standard landline phone services delivered over copper wire. These include single business lines and multi-line services.
ISDN2 (Basic Rate ISDN): Commonly used by small to medium businesses to carry two simultaneous calls on one line. Very widely deployed in Australian business premises over the past 30 years.
ISDN10, ISDN20, and ISDN30 (Primary Rate ISDN): Higher-capacity ISDN services used by larger businesses, call centres, and organisations with significant inbound call volumes.
Traditional fax lines: Fax machines connected via PSTN lines will stop working when Telstra retires copper. Businesses that rely on fax for contracts, compliance documents, or medical records need an alternative.
PSTN-connected alarm systems: Monitored security alarms that dial out over a copper line will fail when Telstra switches off copper. This is a safety issue that businesses frequently overlook during migration planning.
EFTPOS terminals on PSTN: Older EFTPOS terminals that connect via a phone line rather than broadband or 4G will be affected.
How to Tell If Your Business Is Affected
Your business is likely affected if any of the following apply:
You have a Telstra or reseller landline service with a traditional phone number and pay a line rental charge. You have an ISDN service: your phone supplier or Telstra bill will show ISDN2, BRI, PRI, ISDN10, ISDN20, or ISDN30 as the service type. Your business runs a traditional PBX phone system connected to ISDN or PSTN lines. Your security alarm, fax machine, or EFTPOS terminal uses a phone line rather than broadband. You are receiving notifications from Telstra about your copper services being retired.
If you are unsure, check your current phone bill for references to PSTN, ISDN, line rental, or copper. If you see these terms, your business needs to plan a migration.
What Happens If You Do Nothing?
When the PSTN switch-off Australia reaches your area, your existing landline and ISDN services stop working. Telstra provides no automatic replacement. Calls to your business number will fail, and staff cannot make or receive calls on the existing system. If your alarm system or EFTPOS runs on the same line, those will fail too.
Businesses that wait until the last moment often face rushed migrations with poor outcomes: call flows that do not work as intended, staff without phones for days, and customers calling a disconnected number. The switch-off does not move because you are not ready.
What Is the Alternative?
The replacement for PSTN and ISDN is a hosted VoIP (Voice over Internet Protocol) phone system, sometimes called a hosted PBX or cloud phone system. Instead of calls travelling over copper wires, they travel over your existing internet connection.
A well-configured hosted phone system does everything a traditional ISDN system does, and considerably more. Auto attendants, ring groups, call queues, voicemail to email, call recording, after-hours routing, and mobile apps all come standard. Staff can answer calls on a desk phone, a mobile phone, or a laptop, from the office, from home, or from anywhere with internet access.
Critically, hosted phone systems are not tied to a physical location or a copper line. Adding a new office, moving premises, or having staff work remotely requires no hardware changes. You update settings in the cloud, and the system adapts immediately.
What to Look for in a Replacement Provider
Not all hosted phone system providers are equal. Before you commit, ask these questions:
Are there lock-in contracts? Some providers require 24 or 36-month agreements. A provider confident in their service should offer month-to-month terms.
Can you trial the system before committing? A functional trial, not a demo, lets you test real call flows with real numbers before you commit.
What is included in setup and support? Number porting, call flow design, staff training, and ongoing support should be included as standard, not charged as extras.
Is support local? When something goes wrong with your phone system, you want support from someone who answers quickly and knows your setup. Melbourne-based support with a direct phone number is very different from an offshore helpdesk ticket system.
Can the system handle your specific call flows? Generic templates do not suit every business. Look for a provider that builds call flows around how your business actually operates.
Planning Your PSTN Switch-Off Australia Migration
A PSTN switch-off Australia migration does not need to be disruptive if you plan it properly. The general process looks like this:
First, audit your existing services. List every service connected to copper: phone lines, ISDN services, fax, alarm, EFTPOS, any lift or emergency phone. Each needs a migration plan.
Second, select a hosted phone system provider and design your new call flows. How do you want calls to ring? What happens after hours? Who handles which department? This is the right time to improve your call handling, not just replicate the old system.
Third, port your existing numbers. Number porting transfers your current business numbers to the new system so customers reach you on the same numbers. This process takes time, start it well before your copper retirement date.
Fourth, test thoroughly before go-live. Run the new system in parallel with the old system where possible. Have staff test every scenario: incoming calls, transfers, voicemail, mobile apps, after-hours routing.
Fifth, switch over and decommission. Once the new system is confirmed working, cancel the old copper services and remove hardware you no longer need.
The Opportunity in the Disruption
The PSTN switch-off Australia is a forced change, but it is also an opportunity. Many Australian businesses are still running phone systems designed for a different era, systems that tie calls to a desk, require expensive hardware, and make it difficult for remote staff to work effectively.
A modern hosted phone system removes those constraints. Calls follow staff wherever they are. New team members are added in minutes. Opening a second location does not require new phone lines or a site visit from a technician. The system can grow as the business grows.
For businesses that have been putting off updating their phone infrastructure, the copper switch-off is the moment to stop deferring and start building something better.
Frequently Asked Questions
When will the PSTN copper switch-off affect my area?
Telstra is retiring copper progressively by area. The timing varies depending on your location. You should receive advance notice from Telstra when your services are scheduled for retirement. If you have not received notice but have copper services, contact your current phone provider to confirm the timeline for your address.
Can I keep my existing business phone number when I switch to a hosted system?
Yes. Number porting transfers your existing business numbers to the new hosted system. You can port most Australian numbers to the new system, including geographic numbers (03, 02, 07, 08) and 1300 or 1800 numbers. The porting process takes time, so start it well in advance of your copper retirement date.
Hardware and Equipment Questions
Do I need new hardware to switch to a hosted phone system?
Not necessarily. Many businesses use softphone apps on existing smartphones or computers, requiring no new hardware. If you prefer desk phones, modern IP phones from brands like Yealink are typically cost-effective. Older ISDN-connected PBX hardware will not work with a hosted system, and you will need to replace it.
Will my fax machine still work after the copper switch-off?
A fax machine connected to a PSTN copper line will stop working when copper is retired. Options include a cloud fax service (which receives faxes via email), a fax-to-email adapter, or, for many businesses, simply discontinuing fax altogether and using email or secure document portals instead.
What about our security alarm and EFTPOS terminal?
Both need separate migration plans. Security alarms can typically be converted to communicate through an extension configured in your new hosted business phone system. EFTPOS terminals should be reviewed with your bank or payment provider; most modern terminals already use broadband or 4G, or wireless internet.
Is a hosted phone system reliable enough for a business?
Yes. Modern hosted phone systems deliver business-critical reliability, running on redundant cloud infrastructure with no single point of failure. Voice quality over a good broadband connection is equal to or better than traditional copper lines. In the event of a local internet outage, the system automatically diverts calls to mobile phones.
Smart Phone Systems is a Melbourne-based hosted business phone system provider. We help Australian businesses migrate from PSTN and ISDN services to modern cloud phone systems, including call flow design, number porting, staff training, and ongoing support. No lock-in contracts, and a one-month functional trial before you commit. Contact us to discuss your migration.
