Retailers reported a 2.2% fall in sales year-on-year, according to the monthly BDO High Street Sales Tracker.
The riots added to existing high street woes including low consumer confidence, unemployment, pay freezes and the fragile economy to deter shoppers from spending during August, according to the survey.
Retailers in London as well as those in other areas not directly affected by the disruption were also forced to cut trading hours, which ate into performance.
Non-store sales, which include online and phone orders, were 40.2% up year on year, which BDO says should offer further incentive to invest in multichannel operations.
Don Williams, national head of retail and wholesale at BDO, says: “Ever since the recession hit, smart retailers have been working flat out to keep consumers spending in an extremely tough trading environment. But the scale and ferocity of the disruption we saw in August was a real body blow.
“We don’t expect the pressure on consumer confidence to ease – or the cash they have in their pockets to increase – so we’re not expecting the sort of ’keep calm and carry on’ sales uplift that we might see if the economy was in better health.”