The latest Covid-19 milestone is being described as something to celebrate, but comes with a warning that New Zealand can't afford to let its guard down.
In a statement, the Health Ministry said there were still 23 active cases of the coronavirus in managed isolation facilities.
Director-General of Health Dr Ashley Bloomfield thanked everyone who had been tested and those doing the testing.
"Achieving 100 days without community transmission is a significant milestone, however, as we all know, we can't afford to be complacent.
"We have seen overseas how quickly the virus can re-emerge and spread in places where it was previously under control, and we need to be prepared to quickly stamp out any future cases in New Zealand.
"Every person in the team of five million has a role to play in this."
Dr Bloomfield said anyone with symptoms of Covid-19 should seek advice from their GP or Healthline and stay at home.
"Keep a record of your movements so you can refer to them for contact tracing if required.
"Don't let the team down - none of us can afford to do that," Dr Bloomfield said.
The Prime Minister also said today the 100-day mark did not reduce the threat of a second wave of Covid-19.
Jacinda Ardern said while no other country had been in New Zealand's position so far, people should not get complacent.
"In terms of a milestone, yes 100 days is a significant period of time, but it actually doesn't lessen any of the risk, that's daily.
"As long as we of course continue to exist in a world where this pandemic is growing, then risk continues," she said.
Ardern said New Zealand is still having to manage its borders very carefully and people should remain vigilant.
Auckland University professor Shaun Hendy said while it was a big deal, there was still the risk of a second wave of infection.
"Our borders are not completely watertight, we know there's still the possibility the virus could through the borders," he said.
"It's not a time for complacency, but I think it does show the benefits of the elimination strategy that we used early on in fighting the disease."
Hendy said we were playing a long game, with the pandemic likely to be around for at least a year.
Today was the fourth day in a row that there has been no new cases reported in New Zealand.
New Zealand's total number of confirmed cases of Covid-19 remains at 1219.
The country's laboratories processed 4249 tests yesterday, including 542 swabs taken in managed isolation and quarantine facilities.
The Ministry said there was a "very encouraging" number of people coming forward to be tested for the coronavirus at pop-up testing centres run by District Health Boards.
"On Friday there were 133 people swabbed over a two-hour period at New World in New Plymouth. The testing centre in Manurewa had 153 people swabbed yesterday, and 326 people were tested yesterday at the pop-up clinic in Christchurch."
- If you have symptoms of the coronavirus, call the NZ Covid-19 Healthline on 0800 358 5453 (+64 9 358 5453 for international SIMs) or call your GP - don't show up at a medical centre
Read more about the Covid-19 coronavirus:
- See all RNZ Covid-19 news
- Covid-19 symptoms: What they are and how they make you feel
- Touching your Face: Why do we do it and how to stop
- Scientific hand-washing advice to avoid infection
- Your Covid-19 questions answered - from health and employment to managing anxiety
- A timeline: How the coronavirus started, spread and stalled life in New Zealand
- Coronavirus: A glossary of terms