How do I open a bank account as a newcomer to NZ?

You will need proof of identity (a valid passport is accepted everywhere) and proof of address — a recent bank statement, utility bill, or an Immigration NZ letter usually works. You must hold a valid visa. Some banks let you start the application 90-365 days before you arrive, but you typically can't withdraw funds until you complete identity verification in person at a NZ branch. An IRD number isn't always required to open the account, but provide it as soon as you have one so the bank applies the correct tax treatment to any interest earned. Source: major NZ banks' newcomer-banking guidance (e.g. ANZ "Moving to New Zealand").