This paper documents a comprehensive database for the populations of 60 New Zealand towns and cities (henceforth “towns”). Populations are provided for every tenth year from 1926 through to 2006. New Zealand towns have experienced very different growth rates over this period. Economic geography theories posit that people migrate to (and from) places according to a few key factors. In order to analyse the determinants of urban growth empirically, we need a comprehensive database of urban populations over time, as provided here.