The high street was dealt another blow as it emerges footfall in August was 1.6% lower compared with the same period a year ago.
The BRC-Springboard Footfall Monitor also revealed August was a tough month for retail parks, which have traditionally been the one area of bricks-and-mortar stores to hold steady against the online onslaught.
Footfall in retail park locations increased 1.7% year on year, but this was the slowest increase since May and well below the three-month average increase of 2.5%.
Meanwhile, both high streets and shopping centres reported a decline, falling 2.3% and 2.8% respectively.
The 1.6% fall in overall footfall represented a deeper decline than July, when footfall fell 1.1%.
British Retail Consortium director-general Helen Dickinson said: “The continued decline in footfall in shopping centres and on the high street is disappointing, but not surprising.
“The fact that the number of visitors to retail parks has dipped below the three-month average is also a clear sign of a lack-lustre August.
“As we start the long march to Christmas, retailers will want to see an increase in shopper numbers in all store locations.”
The figures for August did not include the bank holiday, which had shoppers flocking to shopping centres and retail parks after a washout.
Footfall dropped 4.1% on high streets on the Sunday, while shopper numbers soared 11% at shopping centres as consumers fled for cover.
Springboard marketing and insights director Diane Wehrle said the August figures are a clear sign high streets and shopping centres “are under increasing pressure once again”.
Wehrle said: “The probability is that in September UK footfall will bounce back from the -1.6% recorded this August to at least equal the more modest 0.9% drop recorded in September 2014.”