Acting Superintendent Gini Welch said a collective commitment was needed to make sure motorists were not driving when they were impaired or distracted, that people wore seatbelts and that they drove within speed limits.
Otago had 25 road deaths in 2020, the highest number in more than a decade, and Southland had 13 more.
Nationally, provisional figures from the Ministry of Transport show there were 320 road deaths in 2020, down 32 on the 2019 figure of 352.
Covid-19 lockdowns appeared to have prevented the national figures from surging higher.
However, there were still fatal crashes during those periods, Supt Welch said.
There had been a sustained moderate reduction in people dying on New Zealand roads since July 2018, she said.
But the numbers of serious crashes and deaths remained much too high.
"We can do better," she said.
Recent road deaths included Invercargill grandparents Kareen and Jim Malcolm, whose motorcycle collided with a milk tanker on the Riverton-Wallacetown Highway on Monday.
Columba College pupil Lucy Williams (17) died on Boxing Day, after spending several weeks on life support at Dunedin Hospital.
A celebration of her life is to be held at the Clinton Community Centre today.
There has also been a series of crashes in the South in the past two days.
One person with serious injuries was taken to Dunedin Hospital on Thursday afternoon after a campervan rolled near the Oamaru Airport.
Yesterday, one person was trapped in their vehicle after a crash on the Crown Range Rd.
Police said two vehicles collided on the road between Queenstown and Wanaka about 2.40pm and one person was initially trapped.
The Otago Regional Rescue Helicopter was called to transport a patient to hospital.
That was one of three crashes in the Queenstown Lakes area yesterday amid wet weather.
Supt Welch said inattention, speed and alcohol contributed to many crashes.
"It’s incredibly sad, and also frustrating.
"Police work hard every day to help prevent death and serious injury on our roads, but we can’t do it alone,’’ Supt Welch said.
"We need everyone in New Zealand to make a simple New Year’s resolution — help prevent further fatalities on our roads.
"You can do that by putting away your phone, ensuring you drive free from alcohol, drugs and fatigue, wear your seatbelt, and drive to the conditions within speed limits.’’
The number of road deaths nationally for the Christmas and New Year holiday period - nine so far - is more than double the previous period’s total.
The holiday period ends at 6am on January 5.
