New car registrations posted an annual fall of 14% in July, a key month for sales where registration plates change, the Society of the Irish Motor Industry said.
SIMI said that 21,213 new cars were registered in July, compared to 24,681 in July 2019.
That brings the registrations for the year to date to 74,069, down from 105,439 this time last year.
Volkswagen was the top selling brand with 8,879 registrations so far this year.
Toyota is in close second place, Hyundai is third, Skoda is fourth and Ford in fifth place.
43.63% of the new registrations were diesel, 37.52% were petrol, 12.31% were hybrid, 3.59% were electric and 2.58% were plug-in hybrid.
The data shows that electric vehicle sales were up 5.18% in July to 771, compared to 733 in July last year.
Used car imports for July have seen a decrease of 6.8% to 8,744 last month, when compared to 9,382 in the same month last year, while year to date imports are down 49.6% to 31,531, from 62,508 in 2019.
Brian Cooke, SIMI Director General said while the July registration period did bring much needed activity back to showrooms, new car sales continue to disappoint, with another monthly fall.
"This is despite the fact that many quarter two sales had been pushed back into the 202 registration plate. Covid-19 on the back of Brexit and an already falling new car market since 2016, now sees new car sales back to recession levels, down 30% year to date. Looking further into the numbers, new car sales will fall for the fourth consecutive year, with a staggering 44% reduction over the last 4 years," he said.
He added, "This slowdown is materially undermining the renewal of the National car fleet, which is not only bad for profitability and regional employment, but is also hampering Ireland's efforts to reduce transport emissions. With the Budget only two months away, we need to see a reduction in VRT, to allow the car market return to normal sustainable levels, which will reduce both the age of the fleet and emissions."