Royal Mail has suspended controversial fines for letters with stamps it deems counterfeit after claims that it was penalising the public for its own inadequate technology. Addressees have been forced to pay a levy of £5 to receive post if Royal Mail suspects that a fake stamp was used by the sender. Hundreds of fines have been issued since barcoded stamps became mandatory last July. Some customers whose letters were surcharged claim that the stamps used were bought from Post Office branches and Royal Mail’s own website and questioned the effectiveness of the scanners used to detect fraud. Others have been warned they risk committing fraud and left out of pocket after sending old-style stamps in to Royal Mail’s stamp swap out scheme. Critics have warned that issue has echoes of the Horizon scandal in which bugs in accounting software led to hundreds of post office operators being accused of fraud. Royal Mail has insisted its technology is “robust” and blamed customers for buying bargain stamps online. However, in a sudden U-turn it today announced that it would suspend issuing surcharges until the end of July while it develops an app to allow customers to authentic their own stamps. Currently, only designated Royal Mail staff have the ability to scan the barcodes. Earlier this month, it told the Guardian that its security system had to be kept in-house to prevent fraudsters exploiting it. The company is also appointing an independent expert to assess whether a stamp is genuine when a customer appeals and plans to work with retailers and online platforms to prevent stamp fraud. Post-bearing suspect stamps will now be returned to sender along with a surcharge where possible. Until now recipients have had to bear the cost if a letter is suspected of having been sent fraudulently. Nick Landon, the chief commercial officer at Royal Mail, said: “The combination of new barcoded stamps with added security features and Royal Mail actively working with retailers, online marketplaces and law enforcement authorities, has led to a 90% reduction in counterfeit stamps. “We want our customers to buy stamps with confidence and always recommend that customers only purchase stamps from Post Offices and other reputable high street retailers, and not to buy stamps online – unless from the official Royal Mail shop.”