Footfall fell for the second consecutive month in May, according to the latest BRC/Springboard Footfall and Vacancies Monitor.
The report said footfall dropped 0.2%, marginally down on the 0.1% fall in April.
High streets reported the largest decline, falling 0.9%, but fared slightly better than in April, when they recorded a 1.4% drop.
Out-of-town locations reported the only rise, 3.3% higher than a year ago, while footfall in shopping centres was down 1.5% on the previous year.
British Retail Consortium director general Helen Dickinson said: “This is the second successive month that footfall has eased back a touch, compared to the same period last year. However, actual retail sales over the period have risen, which points to the continuing impact and popularity of online shopping particularly in non-food categories.
“Many retailers are increasingly adept at harnessing the internet and multi-channel innovations to get through to consumers who might not have time to travel to the shops.”
Last week, the BRC revealed that UK sales were up 0.5% in May, compared to the same month last year, helped by a strong growth in clothing sales.