The 43-year-old man was charged with careless use causing death and two charges of careless use causing injury in relation to Friday's crash in Southland, involving a campervan and a car.
He will appear in Invercargill District Court tomorrow.
The crash happened on the Athol Five Rivers Highway, leaving seven people needing medical treatment, including two German children travelling in the campervan.
Two Southern Institute of Technology students who were in the car were taken to Dunedin Hospital in a critical condition. The 22-year-old woman died on Saturday.
The holiday road toll provisionally stands at seven.
A second person involved in a collision between a car and a milk tanker in the Bay of Plenty yesterday died last night.
The truck and a Volkswagen Golf collided near Paengaroa, at the intersection of State Highway 2 and Wilson Rd, leaving four people trapped in the car.
A 30-year-old man from Rotorua, who was the driver of the vehicle, died at the scene yesterday. Another man from Rotorua, 31, suffered critical injuries in the crash and died at Waikato Hospital at 11.20pm yesterday, police said.
Two female passengers in the car remain in a critical condition. A third man suffered minor injuries.
On Boxing Day a man died after the rental car he was driving collided with another car in Tauranga, critically injuring an elderly couple from Omokoroa.
A 56-year-old motorcyclist died following a crash near Hurunui yesterday morning.
The man was riding a Harley Davidson on State Highway 7, between Culverden and Hanmer Springs, when his machine and a car collided just before 11am, police said.
He was flown to Christchurch Hospital by the Westpac Rescue helicopter but died shortly afterwards.
The death of a man who was electrocuted after a car crashed into a power pole on a rural road in Glentui on Saturday night is being provisionally included, but may yet be discounted from the official toll.
The official holiday road period started at 4pm on Christmas Eve, and runs until 6am on Monday, January 5.
Last year's Christmas-New Year road toll was seven but the official holiday period was three days shorter than this year's.