When consumers return an item they have ordered online, they are legally allowed to claim a refund not only for the price they paid for the product in question, but also for any delivery fees they were charged. However, a report by Money Mail suggests that few people are taking advantage of this right, meaning retailers could be withholding more than £4.1 billion in unclaimed delivery fees.

This new rule was only introduced two years ago as part of the Consumer Contracts Regulations, meaning that many people are entirely unaware that it exists. On average, customers could claim back close to £3 for every item they return, but will usually need to explicitly ask a retailer to include this as part of the overall refund.

Because this cash is not refunded automatically, there are typically a number of other steps which need to be completed in order to ensure that retailers comply with the law. It's emerged that because shoppers are either unfamiliar with their new rights or do not want to go through the hassle of getting in touch with retailers, a lot of cash is going unclaimed.

Retailers, including Asos and Boohoo, which were contacted as part of the study said that their customers could indeed get their shipping fees refunded, but would have to make a specific request.

Campaigners argue that anyone who carries out safe shopping online should be entitled to expect a full refund if they return a product, up to and including any relevant delivery fees, without having to take any extra steps. However, many retailers are unwilling to make things simpler for customers and could continue to cling onto cash which should rightfully be returned, unless further action is taken by industry regulators.