Last year saw 392 people lose their lives on NSW's roads, a marked increase on 2016 and a worrying sign the days of decreasing road tolls are over, the government fears.
An additional 12 people died in 2017 compared to 2016, data by the Toward Zero campaign revealed on Monday.
The number of deaths on NSW roads has increased every year since hitting its lowest point in 2014.
Speed accounted for nine more deaths in 2017 than 2016 while fatigue, alcohol and seatbelts were all linked to fewer deaths.
"In 2017, as with 2016, speed was the biggest killer with 168 people losing their lives because someone was driving too fast," Roads Minister Melinda Pavey said in a statement.
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"That is more than 40 per cent of our road toll."
Country roads claimed 180 lives in 2017, 22 more than the previous year, while 114 people died on motorways, freeways and highways - an increase of 16 over 2016.
The end of the year was particularly deadly leaving police pleading with drivers to slow down and take care during the Christmas period.
It culminated in a horror fatal head-on on the state's south coast in which a driver in one vehicle and three members of a family in another vehicle were killed.
The fourth member of the family, actress Jessica Falkholt, is still clinging to life in a Sydney hospital.
The NSW government noted the number of vehicles registered in the state has increased by 1.2 million in a decade.
Prime Minister Malcolm Turnbull said one death on the roads was too many.
"At this time of year, which should be a time of happiness and love and families getting together, to see so many families being ripped apart by these shocking accidents is a tragedy," he told reporters in Sydney on Monday.
He said the issue was primarily one for state governments to address but the Commonwealth would work to make sure driver training, safety and licensing was improving across the nation.
Pedestrian deaths in NSW have declined from 71 to 54 and fatal crashes involving young adult drivers has also decreased from 57 to 42.
The NSW government attributed the improvements to better pedestrian and bicycle infrastructure and licensing systems for young people respectively.
