Pyrmont Post Office, Commonwealth heritage post office in Pyrmont, Australia.

Pyrmont Post Office is a two-story building at 148 Harris Street designed in Federation Free Style architecture. The structure displays intricate stone work, grand entry arches, substantial window frames, and a complex hipped roof that define its exterior character.

Pyrmont Post Office was designed by the Government Architect's Office under Walter Liberty Vernon, who held that post from 1890 to 1911. It was added to the New South Wales State Heritage Register on 22 December 2000 and to the Australian Commonwealth Heritage List on 22 June 2004. The property is owned by Australia Post, an agency of the Commonwealth Government.

The building's name comes from its Harris Street setting in Pyrmont, not from any square. As a post office it served the peninsula's waterfront workers, and since its closure it has operated as a bank branch, so visitors today enter it for banking rather than postage. It was added to the New South Wales State Heritage Register on 22 December 2000.

The building stands at 148 Harris Street in Pyrmont, an inner suburb of Sydney, not in a town centre. It is a former post office now used as a bank branch, so the interior is not open for sightseeing; the exterior can be viewed from the pavement on Harris Street.

Walter Liberty Vernon designed this building as an exemplar of Federation Free Style architecture featuring exceptionally detailed work. The massive entry arches and complex roof design showcase the craftsmanship of this architectural period.