Total life-for-like fashion sales fell 2.22% year on year for the week to 23 September, the BDO High Street Sales Tracker has shown.
It is the third consecutive week that the category has experienced negative sales growth.
In-store sales in fashion were down by 5.81%, compared to the same week last year.
Overall footfall was down by 3% for the week, its eleventh consecutive week of year-on-year decline,
Footfall on the high street suffered the most, down by 4.7%, while shopping centres also fell, down by 3.1%.
Meanwhile, retail parks saw footfall increase by 0.8%.