The Ministry of Civil Defence will be testing its Emergency Mobile Alert System on Sunday November 25 between 6 and 7pm.
Director of the Ministry of Civil Defence & Emergency Management Sarah Stuart-Black said it is important to ensure the alerts work properly and to prepare the public for what to expect.
"This is just a test, but when emergencies happen, Emergency Mobile Alert will be a vital channel to help keep our communities safe," she said.
"Not all phones are currently capable of receiving the alerts, so we need people to look after each other: if you receive an alert, tell your neighbours, your whanau, your colleagues."
It is expected that half of all phones will be able to receive alerts this time around, compared to a third during last year's test.
An alert last year prompted some controversy when it was sent out accidentally, with no warning and in the early hours of the morning.
Some New Zealanders were woken just after midnight on a weekday last October when the false alert went out, followed by multiple apology notifications before 3am.
Luckily this time the alert will be before most bedtimes, and we have plenty of warning.
Ms Stuart-Black said the alert acts as an additional channel for safety during an emergency, but will not replace radio or internet channels if a natural emergency were to strike.
Check if your phone is compatible here