About 135 managed isolation workers will be redeployed after missing a deadline to be vaccinated for Covid-19.
From 11.59pm today, all workers in managed isolation and quarantine (MIQ) facilities and government agencies at the border must have been vaccinated.
All public and private MIQ workers, contractors and visitors will have to provide proof of vaccination each time they enter a facility from tomorrow, May 1.
But initially, current workers will be considered vaccinated if they have had one dose of the vaccine. All current workers must have had two doses of the vaccine by June 5, 2021.
New workers will need to have their first dose before starting work - they then have 35 days from starting work to receive their second dose.
The new requirement was introduced under the Covid-19 Public Health Response (Vaccinations) Order 2021, and is being lauded as a "big milestone".
Joint head of managed isolation and quarantine Brigadier Jim Bliss said 97 per cent of MIQ workers had been vaccinated.
"We always expected there would be a small percentage who wouldn't [get vaccinated]. On any given day we have around 4500 people working in our 32 MIQ facilities from over 300 different employers.
"Anyone not vaccinated ... will be redeployed by their employer. These are individual employment discussions for employers to have with their employees. We have supported them with assistance from the Ministry for Social Development to explore other employment options.
"This is the largest immunisation programme ever undertaken in this country and MIQ and border workers were first in line. They are among the people most at risk of exposure and I'm really proud so many of them have stepped up and led the way for the country."
New Zealand Customs Service chief executive Christine Stevenson said the new requirements would also apply to workers employed by government agencies at the border who interacted with international arriving air passengers (not including quarantine free travel) and crew or ship's crew, or who spent more than 15 minutes in an enclosed space on board ships.
"Government border agencies will have a duty to ensure that only people who have been vaccinated are permitted to carry out work, or other activities, at our international airports and ports," Stevenson said.
New Zealand's Covid-19 vaccination rollout started on February 20.