West Auckland police have "increasing concern" for a 41-year-old woman and her three-year-old daughter missing since early November.
Toni Reihana and her daughter Keyana have not been in contact with agencies since early last month.
Police believe Ms Reihana may be in hiding in West Auckland or visiting extended family in Hokiana.
"There is increasing concern for her welfare and the wellbeing of her daughter. Multiple enquiries have failed to locate the pair," police said in a statement.
Ms Reihana is described as Maori, 162cm-tall, and of slim to medium build.
Keyana is Maori, with fair complexion and brown hair.
Anyone who has any information about their whereabouts should contact Constable Alison Wilson at Henderson Police on 09 839 0608 or Crime Stoppers on 0800 555 111.