Royal Mail has been slammed for considering ditching the Saturday post.
The privatised postal giant is required by law to deliver six days a week under what is called the universal service obligation.
But the firm has seen a slump in the number of letters it handles because of emails, more billing done online and changing habits.
The coronavirus lockdown saw Royal Mail deliver 1.1billion fewer letters.
It could ask industry regulator Ofcom to drop the requirement for Saturday letter deliveries as part of a review, following the findings into what customers need.
Keith Williams, interim executive chairman at the Royal Mail Group, said in a letter to staff: "These findings tell us the best way to ensure the 'universal service' continues to meet our customers' needs is to rebalance our service model more towards the growing parcels market, particularly urgent parcels, and urgent letters."
Dropping Saturday letter deliveries could be another blow to older people who rely more heavily on the post.
Jan Shortt, of the National Pensioners Convention, said: "Older people, particularly those living alone, as well as other vulnerable groups unable to access online services, will be the most affected by this decision.
"Like those delivering milk and other goods to homes across the country, postal workers are also the eyes and ears of communities, making sure that those known to be alone and vulnerable are staying safe and well.
"Older people, more than any other group in society still rely on the post as their preferred method of their communication.
"Royal Mail may see this as a necessary cost cutting exercise and that one day out of six without post is insignificant, but we would ask them to consider those living alone and that receiving a nice letter, card or parcel on a Saturday morning actually gives them something to look forward to and sees them through until the beginning of the week."
