Auckland Unitary Plan Upzoning — City-Wide Zoning Reform and Its Measured Effect on Permits and Rents

In 2016 Auckland Council made the Auckland Unitary Plan operative, upzoning around three-quarters of residential land to allow medium- and high-density housing and removing many minimum-parking and density constraints.
Peer-reviewed synthetic-control research (Greenaway-McGrevy and co-authors) finds that permitting roughly doubled within five years, with about an 80% increase in permits over six years, concentrated in upzoned areas. A companion study in Economic Inquiry estimates rents were around 23% lower eight years after reform than without it; earlier working-paper estimates ranged 22–35% for three-bedroom dwellings depending on specification.
Caveats: results come from quasi-experimental methods and estimates vary by specification; a review (Land Use Policy) discusses contested claims; much new supply is townhouse infill rather than low-cost housing, and rising construction costs and interest rates limit later gains. The reform is notable for its breadth: city-wide reform differs from limited upzonings that have shown weak effects.

Read the full analysis: https://www.huduser.gov/portal/periodicals/cityscape/vol26num2/ch20.pdf