We’re taught how to call emergency numbers from a young age; whether it be 911 in the US, 999 in the UK, or 000 in Australia. The concept is simple—if you need aid from police, fire, or ambulance, you pick up a phone and dial and help will be sent in short order.
It’s a service many of us have come to rely on; indeed, it’s function can swing the very balance between life or death. Sadly, in Australia, that has come to pass, with a person dying when their Samsung phone failed to reach the Triple Zero (000) emergency line. It has laid bare an obscure technical issue that potentially leaves thousands of lives at risk.
Peril
Australia’s Triple Zero emergency service becoming a hot-button issue. September 2025 saw widespread failures of emergency calls on the Optus network, an incident that was tied to at least three deaths of those unable to reach help. A series of further isolated cases have drawn more attention to edge case failures that have prevented people from reaching emergency services.
A bigger potential issue with the Triple Zero service has since bubbled up with the increased scrutiny on the system’s operation. Namely, the fact that a huge swathe of older Samsung smartphones cannot be trusted to successfully call 000 in an emergency. The potential issue has been on the radar of telcos and authorities since at least 2024. Since then, on November 13 2025, an individual in Sydney passed away after their phone failed to dial the emergency line. Their phone was using a Lebara SIM card, as managed by TPG and using the Vodafone network, when the incident occurred. Subsequent investigation determined that the problem was due to issues already identified with a wide range of Samsung phones.
The issue surrounds the matter of Australia’s shutdown of 3G phone service, which took place from 2023 to 2024. If you had a 3G phone, it would no longer be able to make any calls after the networks were shut down. Common sense would suggest that phones with 4G and 5G connectivity would be fine going forward. However, there was a caveat. There were a number of phones sold that offered 4G or 5G data connections, but could not actually make phone calls on these networks. This was due to manufacturers failing to implement Voice-over-LTE (VoLTE) functionality required to carry voice calls over 4G LTE networks. Alternatively, in some cases, the 4G or 5G handset could make VoLTE calls, but would fail to make emergency calls in certain situations.
Communication Breakdown
It all comes down to the way voice calls work on 4G and 5G. Unlike earlier 2G and 3G cellular networks, 4G and 5G networks are data only. Phone calls are handled through VoLTE, which uses voice-over-IP technology, or using Voice over NR (VoNR) in a purely 5G environment. Either way, the system is a data-based, packet-switched method of connecting a phone call, unlike the circuit-switched methods used for 2G and 3G calling.
The problem with this is that while 2G and 3G emergency calls worked whenever you had a tower nearby, VoLTE calling is more complex and less robust. VoLTE standards don’t guarantee that a given handset will be interoperable with all LTE networks, particularly when roaming. A given handset might only like IPv4, for example, which may be fine in its home region on its regular carrier. However, when roaming, or when doing an emergency call, that handset might find itself only in range of a different network’s towers, which only like IPv6, and thus VoLTE calling will fail. There are any number of other configuration mismatches that can occur between a handset and a network that can also cause VoLTE calling to fail.
Usually, when you’re in range of your phone’s home network with a modern 4G or 5G handset, you won’t have any problems. Your phone will use its VoLTE settings profile to connect and the emergency call will go through. After all, older models with no VoLTE support have by and large been banned from networks already. However, the situation gets more complex if your home network isn’t available. In those cases, it will look to “camp on” to another provider’s network for connectivity. In this case, if the phone’s VoLTE settings aren’t compatible with the rival network, the call may fail to connect, and you might find yourself unable to reach emergency services.
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