Three separate crashes this morning have left five dead north of Taupō, three dead near Ashburton and one dead in Auckland.
Police said 20 people have been killed on New Zealand roads in the past eight days.
Assistant commissioner of road policing and prevention Sandra Venables told Checkpoint it had been a "horrific day".
She said she would not talk about the specifics of today's crashes which were under investigation.
But she said police cannot bring down the road toll alone, and needed everyone's help.
"We just want everyone to drive to the conditions, maintain their focus on the roads, and keep their speeds down, especially if it's a wet wet day."
Five dead in Taupō crash
The crash near the Kinleith Forest, reported at about 8.20am, resulted in the deaths of five people from the same family. The incident involved a single vehicle crash on Tirohanga Road, 30km north of Taupō.
Scott Osmond from Fire and Emergency said a sixth person was taken to hospital by helicopter with serious injuries.
"One of the survivors was trapped in the vehicle and we had to extricate that person and we're still on the scene awaiting the completion of the police inquiry to extricate some of the deceased."
The survivor, an 11-year-old boy, is now stable, but in a serious condition in hospital.
Three die in crash near Ashburton
In a separate incident in the South Island, three people are dead and one has suffered critical injuries following a crash near Ashburton.
Police said two cars crashed at the intersection of Mitcham Road and Hepburns Road shortly after 10am.
A St John spokesperson said two people with critical injuries were taken to Ashburton Hospital, while another person was being treated for minor injuries.
Man dies in Auckland crash
Meanwhile, a man who was critically injured after his car left the road and crashed into the water near Auckland Airport has now died.
Emergency services were called to the intersection of Tom Pearce Drive and Puhinui Road just after 1am.
The man was taken to Middlemore Hospital. The Serious Crash unit is investigating.