The Post Office says it is looking for a new operator for a counter service in the Great Dover Street area after the closure of the McColl's convenience store.
The Post Office in Great Dover Street first opened in 2006 as part of a Costcutter store.
The Costcutter store was later sold to the Co-operative Group and in turn last year was transferred to McColl's.
Although the Post Office service was due to continue until Sunday 10 December, the counter had already closed when SE1's reporter visited on Saturday lunchtime.
In a notice displayed in the shop, Post Office Ltd said: "We are looking to restore a Post Office service in this area, as soon as possible."
In the meantime customers have been directed to use the Post Offices in Old Kent Road and Southwark Bridge Road.
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