Some 165 people were killed in accidents on Ireland's roads during 2015 - a fall of 28 on the previous year.
Although the figure marks a 15% decline and is the second lowest since recording began in 1959, l ast month was the worst December for road deaths since 2007.
Road Safety Authority (RSA) chairwoman Liz O'Donnell said: "It's difficult to describe 2015 as a success when 165 people lost their lives on the roads and especially after the carnage we witnessed in the final weeks of year.
"But the number of people being killed on the road is the only way we can measure success or failure and it's important that people know progress is being made and their efforts are making a difference."
In total, there were 158 fatal collisions during 2015 - a 12% reduction compared with 2014.
Broken down into road user categories, the official figures released by the RSA show that 75 drivers, 27 passengers, 32 pedestrians, 22 motorcyclists and nine cyclists lost their lives on the roads last year.
The victims included 129 men and 36 women.
However, there was a significant reduction in child fatalities - down from 15 in 2014 to three last year.
Of the drivers who were killed, 20 were not wearing seatbelts while a third of passenger fatalities were not belted in.
Young motorists were the most vulnerable, accounting for a quarter of all drivers to die over the last 12 months.
All cyclists killed were aged between 35 and 75, six of whom died on rural roads.
According to the statistics, the most dangerous times on the roads were between 10am and 12 noon and 4pm and 6pm.
Minister for Transport, Tourism and Sport Paschal Donohoe said: "While every death on our roads is one death too many, I sincerely hope that 2015 is a return to the steady progress we were making as a country, up to 2012, to make our roads safer for everybody
"A reduction of 15% in the number of fatalities is a positive development but the number of lives tragically lost, especially in recent weeks, reminds us that we must continue to focus on the most effective ways of reducing the number of deaths and serious injuries on our roads."
The safest year was 2012 when 162 lives were lost.