There are only 3 major telecommunications service providers in Australia: Telstra, Optus and Vodafone. All three networks cover approximately 99% of Australia's population with Vodafone being the lowest of the three at 96%.

These networks all operate their own network infrastructure independently of each other.

Smaller retailers, known as MVNO's or Mobile Virtual Network Operators, buy and resell the network services of these providers under their own brand name and products. Regardless of which MVNO (reseller) you choose, you will most certainly be using the services of the big three providers. Since MVNO's have lower overheads and operating costs, they can pass on the savings to the consumer and offer lower-cost SIM plans.

Mobile networks operate on different bandwidth frequencies measured in megahertz bands, e.g 850mhz, 2100mhz. 3G networks are often referred to by their operating frequency, while 4G and 5G networks are referred to using their frequency band numbers. For example, Band 28 (700MHz) is a 4G frequency band.

Network bands can be split into 2 categories: low-band or high-band. Low Band is generally any spectrum under 1Ghz (1000mhz), while high band is anything above 1Ghz.

Low band frequencies can travel great distances & provide coverage inside buildings / structures but has limited network speed and capacity. High band network frequencies has the advantage of fast speeds / network capacity but at the cost of reduced coverage, and building penetration.

It's important that your phone can support both types of frequencies, which may not be the case for grey-import devices that were not intended or designed for usage in Australia.

Choosing a Phone

Generally speaking the more expensive or higher end the phone, the higher the likelihood it has the capability to support more bands. An iPhone or a Samsung Galaxy S or Z series for example, will support a multitude of network bands used around the world and will have the greatest compatibility with Australian networks.

Some phones that are purchased or imported from overseas, may only have partial support for the frequency bands in use locally. This may impact your ability to make calls, connect to the internet, or maintain a strong / fast connection with the provider. Before purchasing, do your research on the phone's technical specifications to find out what 4G and 5G bands it supports. You should avoid purchasing less well-known smartphone brands (i.e. no-name generic phones from Wish.com or Alibaba) as it may be difficult to find exactly what bands are supported, if there is no reliable information about it published online.

For the best network performance, your phone should support most or all of the bands in use by your chosen telco provider.

• 2G was introduced in the 90’s and was comprised of two different standards – CDMA and TDMA. Here, we used the GSM standard which is based on TDMA, and 80% of subscribers around the world typically use GSM. It is a very old standard that is to be retired, however many countries still use the 2G standard and your phone will often fall back to 2G when 3G or 4G connections aren’t available. On some older phones, you can see a ‘GPRS’ icon or just a single ‘G’. This means you’re using the older 2G network.

2G services have completely shut down in Australia. Older mobile phones using 2G will not operate on any Australian network, and many devices that use GSM for communication, such as alarms, GPS trackers, weather stations etc. will also lose connectivity to the network.

• 3G is an upgrade over the existing 2G GSM networks, with some extensions and improvements, and was relatively easy to adopt as existing 2G towers could be upgraded to provide WCDMA coverage. 3G is a large improvement over 2G because it now not only allows for faster data transmission, but also allowing for simultaneous use of data and voice at the same time.
• Why was it shut down? Compared to 4G and 5G, 3G has limited bandwidth (with theoretical maximum downlink speeds of only 42.2Mbits with DC-HSPA+). Since 2019, Australia's mobile network operators have been preparing to switch off their 3G networks to boost the capacity, speed and reliability of their 4G and 5G networks.
• This process is called spectrum refarming: repurposing a frequency that was initially allocated to one technology for another one. Because the wireless spectrum is a scarce and limited / very expensive resource, refarming allows telco operators to maximize the usage of an underutilized frequency and allocate it to 4G or 5G capacity, improving the performance of the newer networks.

The 3G network frequencies that were in use prior to the end of 2024 are:

1. 850MHz (B5) – Telstra, Vodafone
2. 900MHz (B8) – Optus, Vodafone
3. 2100MHz (B1) – Telstra, Optus, Vodafone

• 3G Networks have now shut down and any phones that lack 4G with Voice Over LTE support will be unable to make or receive phone calls. This includes calls to emergency services (Triple Zero / 000).
• Devices with 3G Cellular (and no 4G) such as smartwatches, alarms, GPS trackers, weather stations and other IoT devices will also lose connectivity to the network.

TPG Telecom/Vodafone has already switched off its 3G mobile network services as of January 2024. Telstra closed their network from 28 October 2024. Optus 3G network was shut down from 28 October 2024.

• Purchasing Guide: Most smartphones manufactured after 2015 should support 4G networks in addition to 3G. However, even if the device has 4G support, it may require a software update to enable Voice Over LTE (VoLTE) so that it may continue to make or receive voice calls on the 4G network, rather than falling back to a non-existent 3G connection. It is highly recommended that you avoid 'grey-market' or imported devices.
• A recent ACMA guideline amendment requires that network providers only provide carriage service to mobile phone that are capable of making 000 emergency calls using a 4G or 5G connection. Phones that fall back to 3G to make emergency calls will be deregistered from the network. Some devices that have been imported from overseas may be affected by this amendment, and are at risk of being deregistered, unless the telecommunication provider has updated it's whitelist to allow the phone to be used on their networks.
• To check if your phone will be affected when the 3G network is switched off, simply SMS ‘3’ to 3498 for free and your service provider will send you a message about your phone’s status. You can also use the AMTA 3G Lookup service and lookup the device IMEI to find out if your device will work with 4G networks.
• According to the Purchasing guide from AMTA, they say: We are warning the public against buying devices from overseas or from retailers that are sourcing handsets that are made for other markets, otherwise known as grey-market devices. These devices may not allow emergency calling once the 3G networks close down. This is because they are not designed to support all the Australian mobile frequency bands, and may not support features like 4G and 5G (VoLTE) emergency calling.

• LTE is the next-step of the evolution of UMTS (3G) and HSDPA (3.5G) is a complete redesign and simplification of 3G network architecture resulting in a marked reduction in transfer latency.
• LTE, shorthand for Long Term Evolution was the predecessor before the mass adoption of true 4G. It indicates a service that provided transfer speeds of 20 to 50mbps, speeds that were 10 times faster than 3G. It was launched in 2011 and for marketing purposes, it was called 4G even though it didn't meet the International Telecommunication Union's minimum standards to be considered a 4G service. True 4G services became available after carriers upgraded the network several years later.
• 4GX or 4G LTE can provide speeds of anywhere between 100mbps to 1gbps, depending on various factors and how the network was built.

The vast majority of calls and data transmissions in Australia now relies on 4G LTE networks and with new features such as carrier aggregation introduced in 2014, devices can connect multiple cellular frequencies at once to increase the data rate (download / upload speeds) significantly.

• What is VoLTE (Voice over LTE)

Voice over Long-Term Evolution or Voice over LTE is a feature that allows devices to place phone calls over the 4G network, rather than falling back on 3G GSM networks. Without VoLTE, placing a phone call causes your phone to temporarily disconnect from the 4G network, then pick up a 3G connection before it can receive / transmits voice data over 3G GSM. With VoLTE, phone calls are placed without disconnecting from the network (eliminating delays) & it also allows you to use 4G/LTE data services, such as web surfing and tethering, without having to disconnect from an ongoing voice call.

Phone made on 4G networks are typically over SIP or session initiated protocol. This technology is quite similar to Skype or Viber. Phone calls made with VoLTE do not use extra data but call minutes. You pay for the voice call service, not the data you use.

VoLTE compatible devices

In order to place a call on VoLTE, your mobile phone's hardware, firmware, software and the carrier that your phone is connected to must support the feature. If you can use 4G or 5G data while on a call, your device is likely to be using VoLTE, as non-VoLTE phones switch to 3G and cannot sustain high-speed data while on a call.

Some imported smartphones phones might not support VoLTE when used in Australia due to software or firmware limitations, and may require manual or 'unofficial' software / firmware updates in order to make them compatible with VoLTE. This however, does not guarantee that your phone will continue to be supported by your provider, as VoLTE implementation is not standardized across different carriers.

For the best compatibility, opt to purchase a phone from a local retailer instead of importing 'grey import' stock from overseas. If purchasing an older / used or refurbished device, be sure to research online or use the AMTA 3G lookup tool to verify VoLTE compatibility.

Some 4G devices may continue to work for voice calls and data but will not be able to make calls to Triple Zero. Most at risk are older 4G devices and devices that were purchased overseas. You may receive a text message from your provider warning you that your service may be impacted or unavailable if your mobile phone does not fully support their networks. Alternative, text ‘3’ to 3498 (for free) to find out if emergency calling is affected.

The below is a list of the various 4G / LTE Bands that your smartphone should ideally support:

• 700MHz (B28) – Telstra, Optus, Vodafone (This band is particularly important as it offers long range connectivity, useful for remote areas)
• 850MHz (B26) – Telstra
• 850MHz (B5) – Telstra, Vodafone
• 1800MHz (B3) – Telstra, Optus, Vodafone
• 2100MHz (B1) – Telstra, Optus, Vodafone
• 2300MHz (B40) – Optus
• 2600MHz (B7) – Telstra, Optus

Note that it's often not enough to match up just a single frequency, as Australian mobile networks are built using multiple frequencies and not all frequencies are available at every location. For the best performance, and for 4G carrier aggregation to work, you should purchase a phone that supports all the LTE bands that the cell network provider uses.

What Information on specifications should I be looking for

The best way to ensure maximum compatibility with Australian carrier networks is to purchase your mobile device from a local retailer, and ensure that that device was designed for the Australian market. (This can also be important for consumer related reasons, such as warranty coverage, & your rights to repair, replacement or refunds under the Australian Consumer law).

Mobile phone manufacturers often produce different versions of a handset to suit the different needs & technologies of different carriers around the world. If purchasing from an importer or from overseas, try to identify model number of the device. You may also perform an IMEI lookup to obtain it's model number.

Googling a specific model number should give you an answer as to what country or region that device was originally intended for. A Samsung Galaxy phone made for the Mainland China market could still be missing some of the network bands in use in Australia.

You also can visit GSM Arena or use Will my Phone work? to perform your research before you buy.

5th generation wireless systems refer to the ongoing deployment of improved networks that use low-band and mid-band sub 6 frequencies, as well as high frequency millimetre wave bands (mmWave) operating up to 60GHz. This can offer a theoretical peak data transfer rate of 20 gigabits per second although real-word performance tests conducted by Telstra in the Gold Coast has shown that their equipment can hit a peak speed of 3Gbps using mmWave bands.

The exact performance of 5G will largely depend on how the infrastructure is built, and which / how many of the different frequency bands you happen to be in range of when using the network.

You can read this article by Venturebeat to further understand how network providers use a combination of low band, mid band and high-band 5G radio spectrums to provide 5G network access.

As 5G allows more devices to connect to the network at the same time compared to 4G, it's expected that 5G can relieve network congestion as smartphone usage continues to grow.

It should be noted that 5G is not expected to fully replace 4G networks: instead, it will coexist with them and provide a faster fixed wireless internet alternative to 'traditional' fixed broadband or nbn. In addition, some MVNO's also do not offer 5G services as they aren't being sold 5G services by their supplying carrier.

To see if 5G is available in your area, simply consult your carrier's 5G Coverage & rollout maps. Note that 5G coverage is more limited compared to 4G, particularly in areas outside of capital cities and large metropolitan areas.

The following is a list of 5G bands currently in use.

• 700MHz (n28) – Optus, Vodafone
• 850MHz (n26) – Telstra
• 850MHz (n5) – Telstra, Vodafone
• 900MHz (n8) – Optus
• 1800MHz (n3) – Vodafone
• 2100MHz (n1) – Optus, Vodafone
• 2300MHz (n40) – Optus
• 2600MHz (n7) – Telstra, Optus
• 3500MHz (n78) – Telstra, Optus, Vodafone
• 26GHz (n258) – Telstra, Optus, Vodafone

Cited sources and recommend reading:

• Whirlpool forums
• 3G Shutdown on ACMA
• https://oztowers.com.au/Bands
• https://www.sony.co.uk/electronics/support/articles/SX570801
• TelcoAntennas.com
• Whistle Out
• Wikpedia
• http://willmyphonework.net/