Residents in parts of the North East claim they have been left without letters for weeks, only discovering piles of undelivered mail when neighbours visited their local sorting office.
Postcodes across North Tyneside and South Shields are among 19 in the region listed by Royal Mail as potentially affected by delays.
Areas in Northumberland and Sunderland also feature in the latest update.
One resident, who lives in North Shields, described how people in their street only realised there was an issue after noticing no one had received post for an extended period.
“It dawned on our street a few days ago that nobody had received letters for what feels like weeks,” they said.
“Because we get Amazon and DPD deliveries, it may have felt like they had.
“But neighbours visited the sorting office, and apparently, there were dozens of letters waiting for them. It is staggering to me that for an organisation that exists to deliver messages to people, it couldn't deliver the message that your mail wouldn't be delivered.”
They added that there had been no communication from Royal Mail warning customers about the disruption.
“Like even a letter through to say ‘bear with us, really sorry about this, but we have delays’, pretty bad really.
"One of our neighbours just had a stroke, and he was waiting for NHS letters that were just sitting there.
“I get this is winter. I get that people might be sick. But we have a lot of older people around here who depend on the Royal Mail, many waiting for letters from the NHS, so to think they've just been sat there is pretty disgraceful.”
Royal Mail has confirmed that 111 postcodes across 38 delivery offices nationwide could experience disruption, with 19 in the North East.
The affected delivery offices and postcodes in the region are:
Ashington DO (Northumberland)
NE22, NE62, NE63, NE64
North Tyneside DO
NE25, NE26, NE27, NE28, NE29, NE30
South Shields DO
NE33, NE34
Sunderland DO
SR1, SR2, SR3, SR4, SR5, SR6, SR9
A spokesperson for Royal Mail said that “adverse weather, including storms Goretti, Ingrid and Chandra in January, alongside higher-than-usual sick absence, has caused some short-term disruption to certain routes”.
They added: “We understand how frustrating it is when a post does not arrive as expected, and we want to reassure people that the vast majority of mail is being delivered as planned. We encourage customers to reach out directly if they experience any issues, and we will happily investigate.”
On its website, Royal Mail states it aims to deliver to all addresses six days a week, but in a small number of local offices, this may temporarily not be possible due to “high levels of sick absence, resourcing, or other local factors”.
“In those cases, we will rotate deliveries to minimise the delay to individual customers,” the company says, adding that targeted support is provided to restore normal service.
Royal Mail also noted that while temporary delays can lead to items arriving together, high-volume senders such as banks and NHS trusts are increasingly using its economy service, which is delivered five days after posting.
Items sent using this service may arrive alongside First or Second Class mail or on the fifth day after postage, meaning some households routinely receive multiple letters at once.
However, residents affected say the issue in their area went beyond mail arriving in batches, with no letters delivered for weeks and significant quantities held at the sorting office.