The clothing and homeware retailer said group total sales in the 20 weeks to Aug 15 were down 19.2%.
It said its headline earnings per share (HEPS) for the period would likely fall by at least 88.6 cents ($0.0514) from the 443.2 cents a year earlier.
HEPS is the main profit measure in South Africa.
"Performance exceeded internal expectations and the group has gained market share for four months in a row to June," the company said in a trading statement.
The retailer reported a 10.4% fall in full-year earnings in June.
($1 = 17.2484 rand)
(Reporting by Emma Rumney; editing by Jason Neely)