Legislation to legalise same-sex marriage passed in Parliament this week has become law.
The Marriage (Definition of Marriage) Amendment Bill passed its third and final reading by 77 votes to 44 on Wednesday night.
The vote made New Zealand the first country in the Asia-Pacific region and the 13th in the world to enshrine marriage equality in law.
The Governor-General gave Royal Assent to the legislation on Friday.
There is a four month wait written into the Act so the Department of Internal Affairs can make the necessary changes to forms, certificates and computer systems.
This means the first date that same-sex couples will be able to marry will be 19 August.