The new cases include an Auckland school bus driver and a second Auckland University of Technology student.
Of the new cases on Saturday, 18 were in Auckland and three in Wellington.
Wastewater testing had found traces of the virus in Warkworth, north of Auckland, as well as in Auckland.
The country's current Alert level four lockdown is in place for the entirety of New Zealand until at least 11.59pm on Tuesday, August 24.
Face coverings are mandatory inside all operating businesses and services, including public transport.
New Zealanders are advised to keep two metres distance from others when leaving their home for exercising, especially if it is difficult to maintain physical distance from others.
More to come …