The Irish new car market was down 17.3 percent compared with last year. New car sales in July, the first for the 222 registration, were down by nearly 22,000.
Electric car sales were buoyant with market share for electric, plug-in hybrids and hybrids reaching nearly 41 percent.
A combination of Brexit, covid and cost of living concerns has combined to put the brakes on sales of new cars.
In the UK new car sales have fallen for the fifth consecutive month and the industry expects this year to be even worse than last, which was at a 30 year low.
Supply issues have also driven down used car sales in the UK. Transactions have stalled as the semiconductor shortage bites.
The number of used cars sold fell by nearly a fifth in the second quarter.