Shoplifting is at its highest level for nine years but only around one in 10 of the crimes are reported to police, figures suggest.
Retailers also claim that organised crime gangs are targeting expensive items and have driven up the cost of the average theft by nearly two-thirds.
The British Retail Consortium's (BRC) annual crime survey found that among 30 retailers, who represent 51% of the retail sector by turnover, there were 631,391 incidents of customer theft in 2012-13, the highest level recorded in the survey for nine years.
Only 9% of these crimes were reported to police, a drop from 12% the previous year, in what the BRC suggests shows a lack of faith in law enforcement.
The report said: "This is an indication of the lack of confidence businesses have in the police response to customer theft and the perception that it is often perceived as a 'victimless' crime and as a result not taken seriously."
The companies surveyed estimated that around a quarter of customer thefts were never detected.
Figures also showed that the average value per theft had increased to £177, a 62% rise on the previous year and again the highest figure for nine years.
Helen Dickinson, director-general of the British Retail Consortium, said: "Theft from stores pushed the direct cost of retail crime up to £511 million last year, 166% higher than five years ago.
"Far from being victimless, we all pay for this increased stealing through higher prices and, increasingly, shop closures."
The survey team wants to see a single definition of "business crime".