The town’s delivery office will shut, with all operations moving to the site in Havant.
Royal Mail states that this decision follows discussions with the Communication Workers Union, noting the growth in electronic communications and online shopping, as well as the decline in letters, as the reason for the move.
It has been confirmed that current jobs will be unaffected by the relocation, and Royal Mail has promised that delivery services will also not be impacted.
The postmen and women who work in the Emsworth delivery office will continue to work in the area, Royal Mail said.
An exact date for the closure of the office has not yet been announced.