The monarchy of New Zealand - also referred to as the Crown in Right of New Zealand, Her Majesty in Right of New Zealand, or the Queen in Right of New Zealand - is the constitutional system of government in which a hereditary monarch is the sovereign and head of state of New Zealand, forming the core of the country's Westminster-style parliamentary democracy. The Crown is thus the foundation of the executive, legislative, and judicial branches of the New Zealand government.
King Charles III, styled King of New Zealand, acceded to the throne upon the death of his mother, Queen Elizabeth II on 9 September 2022 (due to a time zone difference it was 9 September in New Zealand but 8 September in the United Kingdom).
The sovereign did not possess a title unique to New Zealand until the New Zealand Parliament enacted the Royal Titles Act in 1953, altering the style borne by Queen Elizabeth II and giving her the title of "Elizabeth the Second, by the Grace of God of the United Kingdom, New Zealand and Her Other Realms and Territories Queen, Head of the Commonwealth, Defender of the Faith". Since the passage of the Royal Titles Act 1974, the monarch's title in New Zealand as applies to King Charles III is "King Charles the Third, by the Grace of God King of New Zealand and of His Other Realms and Territories, Head of the Commonwealth, Defender of the Faith."
Although the monarch's New Zealand title includes the phrase "Defender of the Faith", neither the monarch nor the governor-general has any religious role in New Zealand; there has never been an established church in the country. This is one of the key differences from the Queen's role in England, where she was Supreme Governor of the Church of England.
The sovereign of New Zealand also serves as monarch to Cook Islands and Niue, territories in free association with New Zealand within the larger Realm of New Zealand. The New Zealand monarchy is unitary throughout all jurisdictions in the realm, with the headship of state being a part of all equally. As such, the sovereignty of Cook Islands and Niue is passed on not by the governor-general or parliament of New Zealand but through the overreaching Crown itself as part of executive, legislative and judicial operations in all three areas. The self-government provisions for the Cook Islands within the Realm of New Zealand allow the monarch to be directly represented as head of state in Cook Islands affairs by the monarch's representative, while the governor-general of New Zealand represents the monarch in matters pertaining to the entire realm. The governor-general (themselves represented by state services commissioner) represents the monarch in Niue, carrying out all the monarch's constitutional and ceremonial duties of state on their behalf. The administrator of the territory of Tokelau is a government official appointed by New Zealand's minister of foreign affairs to represent the New Zealand Government - not the monarch personally.
The monarch of New Zealand separately serves as monarch for a number of other Commonwealth countries known as Commonwealth realms. This developed from the former colonial relationship of these countries to Great Britain, but they are now independent of each other and are legally distinct.