Royal Mail is facing accusations that postal workers are being asked to hide post from senior bosses, to give the appearance that delivery targets are being met.
The postal service is facing criticism that ongoing delays are affecting millions of people across the UK, and that parcels are being prioritised over letters.
Ten postal workers told the BBC that they are often told by managers to “take the mail for a ride” when a senior manager comes in to inspect the office.
One worker, who spoke on condition of anonymity, said: “Say we have a senior manager coming in from outside the delivery office, any mail that has been left would get hidden by the line managers.
“It gets put into a york [trolley] and taken somewhere, and brought back to you the next day.”
He explained that when someone raises the fact that they have too many parcels to deliver to be able to take out the post as well, staff would often just say “take the mail for a ride”.

“If someone comes in from the outside it looks like you’ve cleared the round, when in actual fact you’ll be bringing it straight back when you finish.
“It’s embarrassing and deceitful,” he said.
Concerns were raised earlier in March that Royal Mail is not meeting Ofcom targets for timeliness in its deliveries, potentially leading to millions of letters arriving late.
There is a legal obligation to deliver first class post six days a week, with signs appearing in certain post offices to remind staff it must be delivered.
Another worker said the phrase “taking the mail for a ride” meant, “if inspections were carried out at the delivery office the first-class mail would not be in the frame.
“This meant the round could be classed as complete… to manipulate the delivery success of the office.”
Labour MP Dave Robertson previously said people in his constituency are “sick of being lied to by Royal Mail”.
The Lichfield MP said on Wednesday: “I met Royal Mail just before Christmas to complain to them about the total lack of a postal service that we have in Lichfield. We were probably the worst area in the country at that point.
“I was told when I had that meeting that all of the first-class mail went out that week. That is a lie, it is an absolute lie, because my constituents told me.

“Royal Mail clearly don’t have a handle on this – they are either not measuring their performance or they are covering up their performance.”
In February, the service said 91.6 per cent of second-class mail was delivered within three working days, while 77.5 per cent of first-class post was delivered the next working day between 29 September and 30 November.
Communication Workers Union general secretary Dave Ward said: “These results prove conclusively that the company’s failure to deliver for customers is a long-term problem.
“These failures are due to a recruitment crisis that has been caused by the decision to impose low wages and poor conditions on new starters in 2022.
“This devaluing of a postal worker’s job, combined with a toxic managerial culture, has created chaos and demoralisation in almost every workplace across the country.”
A Royal Mail spokesperson said: “These claims do not reflect how our delivery operations work and we would take any suggestion that colleagues are hiding mail very seriously.
“We deliver 92 per cent of letters on time and have a range of measures to monitor service performance across our network, including technology to track mail, independent measurement and around 100 unannounced spot checks every week to make sure reporting is accurate.”
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