Retailers have called on the Government, police and courts to get tougher on thieves after the year-on-year cost of theft to the High Street rose from 99m to 137m.
Although the number of shoplifting offences fell by more than 10 per cent in 2009-10, the average price tag of items stolen in a single theft increased from 45 to 70.
The British Retail Consortium (BRC) said it believed organised criminal gangs were responsible for the soaring figure as they target more valuable goods like televisions, computer games and perfumes.
Its survey also uncovered rising levels of theft by employees, costing the industry more than criminal damage and robbery combined.
BRC director general Stephen Robertson said the fall in total offences reflected stores' increased investment in security measures.
Retailers were forced to spend more than 210m on protecting their staff, stock and premises in 2009-10, 10 per cent more than the year before.
Another reason for the fall in offences was the country's economic uncertainty. Security guards had fewer shoppers to monitor, making it more difficult for thieves to strike.
Mr Robertson said: "Faced with soaring retail crime in recent years – boosted by the recession and insufficient action by the police and courts – retailers dug deeper into their own pockets and spent even more on crime prevention measures.
"It's encouraging to see this having a positive impact on the number of shoplifting offences but the cost to retailers still went up.
"Retailers' extra investment in stopping crime has deterred a lot of opportunist thefts leaving a higher proportion of determined, organised thieves who take a greater value of goods each time they steal. At the same time, that investment has revealed more incidents of staff theft."
More than 18,000 staff reported suffering verbal or physical abuse last year, and the BRC urged authorities to do more to protect them.
It demanded urgent action against shoplifters who fail to pay fines and called for persistent and serious offenders to be dealt with by the courts.
Retailers also suggested the creation of a dedicated national unit to investigate and report e-crime and fraud.
Mr Robertson said: "With police resources under pressure, retailers are making a 210m-a-year investment in crime prevention.
"They are tackling shop crime head on.
"With proper support from the courts, police and politicians the fall in crime figures can and should be accompanied by the fall in costs that retailers and their customers deserve."
Shoplifting accounted for about three-quarters of the total cost of retail crime in 2009-10, but the BRC said under-reporting was a problem with only 12 per cent of recorded offences passed on to the police.
Although the survey recorded 482,831 incidents, researchers said the actual figure was likely to be far higher – "in the region of 750,000 to 1 million offences or even as high as 2 million if grossed up to account for the whole industry."
The figures were based on a survey of 54 retailers who employ more than 1.3 million staff and represent almost half of Britain's retail turnover.
Respondents included supermarkets, department stores,
clothing shops, DIY stores, newsagents, chemists and garden centres.