Hi @theandroidkid ,
Searching online indicates that if the phone was already connected to a Australian network and had been used for making/receiving calls and has also been network unlocked then it should be OK to use in NZ with a NZ SIM card.
I would also suspect the Aust. / NZ would be regarded as being in the same “region”, given the regions are very big areas e.g. Asia, Europe, North America, Middle East etc.
Just make sure that the phone is compatible with the network that you want to connect to in NZ which no doubt it will be
2G bands GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 (dual-SIM model only)
3G bands HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100
4G bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 26, 28, 38, 40, 41, 66
Speed HSPA 42.2/5.76 Mbps, LTE-A (3CA) Cat11 600/75 Mbps
Have you seen this regarding travelling to NZ?
“Still current at:16 May 2020
Updated:14 May 2020
Latest update:If you're in New Zealand and want to leave we recommend you do so now while commercial options are available. Follow the Australian High Commission New Zealand on social media for regular updates. If you're an Australian normally resident in New Zealand you can return but you'll be required to isolate for 14 days in either quarantine or a managed isolation facility in your arrival city. This includes if you're travelling on a yacht or other small craft. If you're in New Zealand, minimise your risk of exposure to COVID-19. Follow the advice of local authorities and stay in touch with family and friends so they know you're safe and well.
Our level of advice has not changed:
Do not travel to New Zealand”