New figures from the Central Statistics Office show that the volume of retail sales edged 0.1% lower in November on a monthly basis.
But retail sales were up 3.6% on an annual basis, the CSO added.
The figures were lower than expected.
When car sales are excluded, the CSO said that monthly retail sales rose by 0.2% in November compared to October while there was an increase of 1.9% in the annual figure.
Today's figures show that sales of electrical goods jumped by 6.8% on the back of Black Friday promotions, while sales in bars also rose by 4.1%.
The sectors which saw the biggest monthly decrease in sales included pharmaceuticals, medical and cosmetic articles which fell by 7.5% while sales of food, beverages and tobacco were down 5.6%.
The CSO also said the value of retail sales in November was unchanged from October, while there was an annual increase of 2.7%.
In the first eleven months of 2018, retail sales are up 3.9% on average on the same time the previous year.
Commenting on today's figures, Merrion economist Alan McQuaid said that retail sales continue to remain erratic on a monthly basis and are still swinging back and forth, but the underlying trend is positive.
"Even with the fluctuation in consumer sentiment, overall personal spending has been positive in the past couple of years, boosted by the increase in the numbers employed in the country," he said.
The economist predicted that personal spending will post another positive increase for the whole of 2018 as the unemployment rate continues to drop and disposable incomes rise.
"Following these latest figures, we now think both headline and core sales will post an increase of between 3.5-4%. Looking ahead to this year, a lower spending rise of 2-3% is envisaged for the two measures," he added.