New Malden Post Office will lose three members of staff through plans to modernise the service.
One full-time and two part-time employees have accepted voluntary redundancy at the High Street branch and will be leaving in the next few months.
A Post Office spokesman said: “This revision of staff duties is in line with current business levels, and we would like to assure customers that they will still benefit from quality service from trained staff.”
He added that two new self-service kiosks will be added to the post office in May.
But customer Fran O’Brien, of Selwyn Road, New Malden, said: “It is a loss to the community and it is a shame.
“You need to be able to go in and talk to somebody.
“There are also a lot of people that find using a machine difficult, and if you get one or two members of staff trying to help, there are going to be a lot of people waiting.”
Beverley ward Councillor Terry Paton said: “I cannot support anyone losing their jobs, but when a company has been privatised it wants to maximise its profits.”
Visit the petition to stop the cuts at you.38degrees.org.uk/petitions/stop-staff-cuts-at-new-malden-post-office.