Online shoppers who do not collect their parcels on time could be targeted by scammers.
Undelivered packages from Royal Mail and Hermes are sold on to to third-party companies, who often list the unopened items on eBay.
And experts have said this could result in your name and address being exposed to fraudsters, putting you at risk of identity theft.
Consumer lawyer Gary Rycroft advised people to always collect a parcel.
He told us: "Always collect a parcel because if you don’t your personal details may well be at risk of falling into the hands of fraudsters.
"Fraudsters do target the auction sales of uncollected parcels as it is rich pickings for them to collect raw data on you which they then use to scam you."
Martyn James from Resolver group added: "Most people will be shocked to learn that their undelivered items are being flogged in 'packages' on eBay.
"But it's absolutely outrageous if personal details are still on the packages."
We found three active eBay listings this week.
Each advert showed parcels laid out on the floor, with dozens of bids being placed.
One was titled "5 unclaimed pacels (Royal Mail/Hermes)" and claimed the items were in the original packaging.
The addresses have been blurred out for the listing but the labels remained on the packages.
A quick search on the site shows that some sellers have charged up to £140 for unopened items.
Royal Mail said each year 500,000 parcels are undeliverable because they are either incorrectly addressed or have no address or the intended recipient has moved.
A spokesman said around 15 per cent of undeliverable items were sold off.
Shoppers have also been warned against bidding on items as they may end up paying over the odds for the items.
A Hermes spokesperson said: "Hermes has no role in deciding what then happens to these returned items - they belong to the retailer - and the retailer or their representative decides on the next course of action."
The delivery company also said: "This is the kind of scam which we are unfortunately seeing more often and we would urge buyers to beware.
"Our loss prevention team monitors these scams where possible."
Royal Mail items are usually kept at a sorting office for three weeks.
If they are not claimed they are usually returned to the sender's address - but if there is no address then it is then sent to a returns centre.
Items are held for an additional month - but after that it may be sold on.
The company said they advised firms to remove consumer details and any reference to themselves.
A Royal Mail spokesperson said: "Where we have been made aware of items being sold in this way, we also ask these companies to remove any customer details on the sites as well as make no reference to Royal Mail and to black out our branding."
eBay said: “These listings would be banned under our chance listings policy, which states that all sellers must identify the exact contents of the package in the description."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereLast Updated:
Report this comment Cancel