Marama Davidson gave an emotional victory speech to the Green Party as early election results showed them picking up 10 seats.
Polls earlier in the year showed the Greens might fall out of Parliament entirely, but instead they have surged to a preliminary result of 8 percent.
Party co-leader Marama Davidson said she was "so proud to be standing here tonight" and congratulated Jacinda Ardern and Labour for an "extraordinary win".
"Results show how much New Zealanders want a strong truly progressive Government," she said.
"On behalf of the Green Party, James and I, and all of our wonderful MPs, we are beyond thrilled to be able to say we did it!"
Davidson said the result was both an honour and responsibility.
"We know we can have an Aotearoa where everyone has what they need," she said.
Green Party MP Golriz Ghahraman said the results made her feel "inspired".
"There's been so many personal connections made this campaign and we've done it under COVID, I love that," she told media. "It's a people's movement."