One NZ has released a graphic of its shutdown timetable.

All three of New Zealand’s mobile network operators are shuttering their older 3G networks to concentrate on the new 4G and 5G.

Spark earlier delayed its shutdown until March 31 next year.

While 3G usage on these sites is already very low, the shutdown will impact anyone still relying on an older 3G-only device – including mobile phones, tablets, medical alarms and security systems, 2degrees said.

Chief executive Mark Callander said the telco has been communicating with all affected customers for months, but expects some Kiwis will wait until the last minute to upgrade. He is urging people to:

“3G is an old technology now, and it’s being closed down internationally. The next generation of mobile services – 4G and 5G – are designed for modern mobile use, whether that’s streaming, video calls, or running multiple apps and programmes all requiring data,” Callander said.

“Modern networks need to be faster, more resilient, and more sustainable. 3G simply can’t deliver the performance New Zealand now relies on.”

Shutdown will impact more than phones

While 3G-only mobile phones are the most obvious pain point, the extra three months will be a boon to owners and operators of car navigation systems, smart meters, home alarms, e-readers, vehicle trackers, remote-controlled electric gates and medical apparatus, among other connected gadgets, in order to check if their device runs on the older mobile technology.

No 111 calls

“Phones that rely on 3G technology won’t connect to any networks after the shutdown, including making a 111 emergency call,” Telecommunications Carriers Forum (TCF) chief executive Paul Brislen said.

3G mobile networks were introduced in the 2000s, and Apple launched its first 4G-capable iPhone back in 2012.

But mid-year, the Telecommunications Carriers Forum warned that some newer 4G phones did not support the VoLTE, the 4G calling technology used by 2degrees, Spark and One NZ for voice calls over 4G in New Zealand – particularly models sold by parallel importers.

Retailers shouldn’t be selling a product with a limited lifespan, TCF chief executive Brislen said. The mobile network operators first announced their “end of 2025″ deadline in 2023.

Xiaomi “4G” phones sold by PB Tech, Mighty Ape and Parallel Imported were a pain point until a VoLTE fix was delivered in July.

Some Kindles will be crimped

Many makers of so-called internet of things (IoT) devices have kept using 3G regardless – or kept it on for a long time – because they had low mobile data needs.

For example, any Amazon Kindle bought before 2021 downloads e-books via 3G if out of Wi-Fi range (really old Kindles – from 2009 or earlier – don’t have the option to connect to a Wi-Fi network).

And RNZ highlighted the case of a Christchurch woman who bought a gate in 2024. She recently discovered its cellular remote-control function would no longer work after the 3G shutdown. An upgrade would cost $1000.

Some IoT devices can also run on 2G. There is one 2G network left in the country – run by One NZ – which will be switched off on the same day as its 3G network.

Brislen said people should check with a retailer or manufacturer as soon as possible if a device will work after the 3G shutdown. Service and support could be trickier in the first week of January as urban shutdowns kick in but many device makers or sellers are on limited staffing over the summer.

Complaints to watchdog

The Commerce Commission has received a number of complaints relating to products’ workability after the 3G shutdown, its general manager, fair trading, competition and credit Vanessa Horne said.

The majority of inquiries received relate to mobile phones losing functionality, Horne said.

But there are also complaints about vehicle monitors, an agricultural GPS and reporting system and a home security system.

“Under the Fair Trading Act, traders should not mislead consumers about the products and services that they sell. Traders should inform consumers of any upcoming changes when selling devices that may no longer work once the changes to 3G are implemented,” Horne said.

“If consumers are not informed of these changes at time of purchase, this could raise concerns under the Fair Trading Act.

“The CGA [Consumer Guarantees Act] guarantees that products should be of acceptable quality and be fit for their purpose, for a reasonable amount of time,” Horne said.

How to find out if your phone will survive the 3G shutdown

2degrees’ Callander said his telco began selling 4G phones in 2018. It had only sold 4G or 5G models since 2022.

Spark said the following are the most common 3G phones on its network:

Spark says closing its 3G network “will free up limited radio spectrum to support the expansion of 5G and allow for continued investment in Spark’s 4G network across Aotearoa”.

While mobile users can still experience “4G drop out” – where their phone steps down to 3G because they move out of range of a 4G or 5G-capable celltower, all three mobile players say upgrades will eliminate this problem by the time they switch off their respective 3G networks.

Chris Keall is an Auckland-based member of the Herald’s business team. He joined the Herald in 2018 and is the technology editor and a senior business writer.