Green Party co-leaders Russel Norman and Metiria Turei were in a defiant mood despite polling about a third less votes than they had hoped for.
The duo met with thunderous applause when they arrived at the party election night HQ in Auckland just after 10pm.
The Greens had targeted polling 15 per cent, but fell well short.
"It is true we may not have changed the government tonight but we have made history," Mrs Turei said.
"We have proved we can lead the opposition and we will hold this government to account and will restrain their excesses."
Dr Norman insisted the party had held its ground but conceded it had not achieved as much growth as had been hoped for.
"I would like to say to the one in ten people who voted for us that we guarantee we will stand up for the next three years and represent you in parliament."
Read more of the Herald's election coverage here:
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• Cunliffe vows to stay on as Labour leader
• John Armstrong: Utter triumph for John Key
• Kim Dotcom says he 'poisoned' Internet-Mana
• Winston Peters hits out at National after big poll surge