Royal Mail has announced that it is experiencing disruption across its depots - including in its Swindon and Wiltshire sorting offices.
The postal service has said that the delays are a result of staffing issues caused by Covid and illness among several factors.
It has said that deliveries across the country are operating as normal but there are a few issues affecting local depots.
Other issues affecting deliveries across Swindon include resourcing and other local factors, the Royal Mail has confirmed.
Deliveries will be rotated where there are issues to help minimise delays to customers.
A spokesman said: "We aim to deliver to all addresses we have mail for, six days a week.
"In a small number of local offices this may temporarily not be possible due to local issues such as COVID-related self isolation, high levels of sick absence, resourcing, or other local factors.
"In those cases we will rotate deliveries to minimise the delay to individual customers.
"We also provide targeted support to those offices to address their challenges and restore our service to the high standard our customers would normally receive.
"We're sorry for any inconvenience and thank you for your understanding.
"We will regularly update customers on the offices most impacted."
Wiltshire Postcodes affected by Royal Mail delays
Wootton Bassett
SN4 - See all the postcodes across the SN4 postcode area.
SN16 - See all the postcodes across the SN16 postcode area.
Swindon West
SN5 - See all the postcodes across the SN5 postcode area.
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