Postcodes here are unofficial: they come from open_nz_postcodes (CC0), not NZ Post, and a few may be wrong. Addresses are from LINZ (CC BY 4.0). Spotted a wrong postcode? Report it through the API.
Add New Zealand address look-up to your forms
Every address in New Zealand, as-you-type, with its postcode. Free plan, no card: your API key arrives by email.