Wellington's mayor Justin Lester will welcome them alongside the Prime Minister and other dignitaries.
Prince Harry and Meghan wasted no time kicking off their charm offensive just hours after landing in Sydney by announcing the global headline-grabbing news that they are expecting a baby.
They were greeted at the airport by Prime Minister Jacinda Arden, having flown in from Australia with the Kiwi Invictus team. "The Duke and Duchess of Sussex will both speak at the ceremony this evening", the tweet read, giving photo credit to Markle herself.
The function was created to celebrate the suffrage anniversary, and Dame Patsy Reddy also got a cheer when she pointed out that she was the nation's third female governor general and Arden was the third female prime minister. Both had remembrance poppy pins on their chests.More news: Virat Kohli fastest-ever to reach 10000 ODI runs
As the group of boys put on their show, complete with mosquito-like buzzing noises and group choreography, Markle was spotted laughing and sharing in the moment with Prince Harry, seated next to her.
A Government House representative said a vegetable steamer may have been responsible for the alarm sounding.
She said: "The achievements of the women of New Zealand who campaigned for their right to vote, and were the first in the world to achieve it, are universally admired".
They will leave New Zealand on Thursday.
Also among the crowd was Jan Richardson who opted for a more direct approach when asking the duke and duchess for a picture.
Harry Smith, 7, arrived at Pukeahu National War Memorial at 8.30am in hope of meeting his namesake, Prince Harry.
The event, where the pair will be giving speeches, promises to be a celebration of the outstanding achievements and inspiring spirit of the Invictus Games competitors.