With 69 percent of the votes counted, National has just 26.9 percent of the vote. At that number, it would have just 12 list seats and 35 total seats, meaning many of its MPs will be out of a job.
Speaking to supporters in Auckland's Westhaven this evening, Collins said "we always knew it was going to be tough", as she thanked supporters.
"You've done everything we asked you to. Thank you to everyone who voted National. The next three years will be an opportunity for us to repay that trust."
She thanked all the candidates who had not been successful, saying it took a lot of hard work to put your hand up and go for it.
She also thanked her husband David and son James. "Thank you for picking up the load when I was working every day and night. Thank you for lifting that load off me so I could give everything to the campaign."
She thanked party president Peter Goodfellow for his "unrelenting devotion to the cause", to the campaign team and deputy Gerry Brownlee.
All information on the party's website appears to have been removed, and its Twitter account has been made private.
