Greek retail sales by volume declined by 2.6 percent in August compared to the same month a year ago after a downwardly revised 9.5 percent increase in July, statistics service ELSTAT said on Monday.
Retail sales were led lower by fuels, lubricants, foods, beverages and household appliances, the data showed.
Retailers launched seasonal discounts in July up to end August.
Data on gross domestic product showed weakness in Greek consumer spending in the second quarter, when the economy expanded by 0.2 percent compared to the first three months of the year.
Consumption declined 0.2 percent quarter-on-quarter in April-to-June, hurt by tax hikes.