Four of Southwark’s train stations run by Govia could lose their ticket offices in June.
Denmark Hill, Peckham Rye, Queen’s Road and Gipsy Hill are among 26 London stations that could all be left only with ticket machines.
Mick Cash, the general secretary of the Rail and Maritime Transport Union (RMT) which represents railway staff, said the changes would “would unleash a wave of ticket office carnage”.
“It is clear that Govia couldn’t give two hoots about passenger services, jobs and safety and are prepared to milk these routes for every single penny that they can extract regardless of what the travelling public think of them,” he said.
A spokesman for Govia, said: “Where sales from ticket offices are low, we want to bring staff from behind the windows and on to the concourse to work where they’re needed most, providing assistance and helping sell tickets from ticket machines and their own handheld devices.”