Prime Minister Jacinda Ardern, Governor-General Cindy Kiro and Speaker Adrian Rurawhe led the Proclamation of Accession on Sunday.
It was read by Herald of Arms Phillip O'Shea on behalf of Ms Ardern, Ms Kiro and the Executive Council.
"God Save the King," Mr O'Shea said.
Kura Moeahu, the parliamentary kaumatua (respected elder), also read the proclamation in te reo Maori.
Ms Ardern, speaking in front of several hundred Kiwis gathered on parliament's lawns, said New Zealand had "entered a time of change".
"For seventy years Queen Elizabeth served the people of Aotearoa New Zealand with unwavering duty. For the vast majority of New Zealanders, she is the only monarch we have known.
"We are forever grateful for her close bond."
The 15-minute ceremony ended with a singing of the United Kingdom's national anthem, God Save The King, and a 21-gun salute.
It also provided a rare public outing for Ms Ardern's four-year-old daughter Neve, who accompanied the prime minister and her fiance Clarke Gayford.
On Monday, cabinet will consider arrangements for a state memorial service or possible public holiday, as well as New Zealand's representation at the state funeral on September 19.
Ms Ardern had already announced travel to the United States at that time to attend the United Nations General Assembly.
Australian Prime Minister Anthony Albanese, who announced a September 22 public holiday to honour the Queen, has offered NZ and Pacific nations space on the Australian Defence Force jet travelling to London.
