The number of shop openings fell 15% in the first six months of this year, though closures also fell by 5%.
Shop closures outstripped openings by 1,997 from January to the end of June, according to the Local Data Company.
Vacancy rates began to rise at the end of June after declining steadily since early 2012.
Matthew Hopkinson, the director of LDC, said: “Growth slackened significantly in the half year leading up to the referendum at the end of June, taking the steam out of the gentle improvement in vacancy. Since the end of June we have seen the vacancy rate in leisure outlets inch upwards.”
Hopkinson said there were more challenges ahead, adding: “Increased costs for retailers coupled with fierce competition and oversupply of shops is likely to see increased levels of distress and failure among retailers, with survival of the fittest being the order of the day.”
His warning comes after figures for August from the British Retail Consortium and Springboard, which showed eating and drinking out fuelling footfall to high streets as the number of visitors to shopping centres fell 1.9%.
The LDC report, based on visits to 2,700 towns and cities, exposed a gulf between the towns with the most vacant shops and those with the fewest. Beaconsfield in Buckinghamshire had no empty shops, while a third of those in Burslem, Stoke-on-Trent, had no occupant.
The north-east is the region with the highest percentage of long-term vacant units, LDC said, while vacancy rates were higher in Wales, at 15.1%, than in Scotland, at 12.1%, and England with 11.3%.