The Emergency Mobile Alert system will be tested between 6pm and 7pm on Sunday.
The Government says more than 90 percent of New Zealanders are expected to receive the alert, which is used during disasters to warn people whose life, health or property may be in danger.
It's the fifth annual test of the system, but Emergency Management Minister Kieran McAnulty said it "can come as a shock to some" so is advising those aware of the upcoming test to tell their family member.
"Most of us will be familiar with the system and alert sound," he said. "Most people would have already received them before in a real-life emergency, whether that’s a tsunami, severe weather, a fire, a chemical leak, a boil water notice, or a COVID-19 alert level rise."
The test is a way to check the system, cell towers and individuals' phones' ability to receive the alert.
"Emergency Mobile Alert uses internationally proven cell broadcast technology, meaning there is no need to subscribe or download an app – all you need is a mobile phone capable of receiving Emergency Mobile Alerts, and a network signal," McAnulty said.
"In an emergency, an alert may be sent to target areas affected by serious hazards. If you get an alert, stop, and read the message, and take it seriously. It will tell you what the emergency is and what to do. It will also tell you which agency sent the message and, if needed where to go for more information."
A 2022 disaster preparedness survey found 95 percent of Kiwis either received the test alert themselves that year or were near someone who did.
McAnulty said that was "really good coverage" and expects a similar proportion this year.
However, he said no system is completely failsafe and Kiwis should still rely on other channels, like radio and social media in times of disaster, or act upon natural warning signs.
"If you feel your life is in danger, don’t wait for an official warning. For example, remember – if you are near the coast and an earthquake is 'Long or Strong, Get Gone'," he said.
Previous tests were conducted in 2017, 2018, 2019, and 2022. Tests in 2020 and 2021 were cancelled due to the COVID-19 pandemic, though a number of alerts were sent out those years about changes in alert levels and restrictions.
