Prime Minister Jacinda Ardern announced the move on Monday, saying the most important thing to communicate about the traffic light system was "for the most part, if you're vaccinated, you can go about doing all the kinds of things you'd usually expect ... what varies is just how large those gatherings are at different levels".
So what is the traffic light system - formally the Covid-19 Protection Framework - and how does it work?
Here are the basics:
The system will involve three settings - green, orange and red.
Vaccine levels will play a key determining factor for which regions go into red and which go into orange on December 3, Ardern says.
"We will look at ... vaccine rates, we will look at case rates, and that will be the major determining factor but we'll also be pragmatic. So you know, a good indication is if you've hit 90 percent first dose is a good indication of where you're heading."
"If you want to be guaranteed that no matter the setting that we are in, that you can go to bars, restaurants and close-proximity businesses like a hairdresser, then you will need to be vaccinated," Ardern told media in October.
Back then, Ardern also said the vaccination certificates would allow businesses to be able to open and operate at any level.
The red setting will allow hospitality to open with vaccine certificates, but gathering limits, physical distancing, masks and other public health measures would be used.
Record keeping and scanning will be required, with face coverings mandatory on flights, public transport, in taxis, retail, and in venues.
Public facilities can open with up to 100 people and 1m distancing. Retail needs to have 1m distancing too.
People are advised to work at home, but ECEs, schools and kura can open with public health measures.
Some outdoor community events will be allowed with limited capacity.
At orange, gathering limits can lift. Places that choose not to use vaccination certificates will either be closed or have public health measures in place.
There will be no limits for the following if vaccination certificates are used: Hospitality, gatherings (weddings, worship, marae), events, close contact business, gyms.
Without the use of certificates, hospitality and gatherings will have limits applied
Without the use of certificates, events, gyms and close contact businesses will not be able to operate.
Green is when there are some Covid-19 cases in the community but at low levels.
Fully vaccinated people can enjoy all events and hospitality and gatherings by showing a vaccine certificate.
Premises choosing not to use certificates will face restrictions similar to the current alert level framework.