The number of families on the waiting list for state houses has jumped by more than 300 in the past three months.
Housing New Zealand figures show 3200 families were on the waiting list in March compared with nearly 2900 in December last year.
Over the same period, the number of vacant, ready-to-let state homes rose from 1776 to 1873.
Housing New Zealand says the vacancies are part of a usual rental cycle and include homes in the process of being let or being assessed for repairs.
But the Labour Party's housing spokesperson, Phil Twyford, says the figures are worrying and indicate something is wrong with the way Housing New Zealand is managing the situation.