The Ahaura Post Office (Former), built in 1894 to replace an earlier building destroyed by fire, was an important part of the infrastructure in this once bustling West Coast town. It has a notably intact exterior and is reportedly the only post office of this type remaining on the West Coast.

Ahaura township was established in about 1863, as it was a suitable landing place for barges at the confluence of the Grey and Ahaura Rivers. After a severe flood in January 1871, the township shifted to higher ground. By this time, the West Coast gold rushes were at their height and thousands of men were working claims nearby. The flourishing township of Ahaura boasted numerous drinking houses and stores, a bakery, police station and courthouse, several lawyers and doctors, a bank and a post office. The first post office at Ahaura opened in 1867, though it was moved to a new site after the floods of 1871. A telegraph and money order office opened in July 1873.

The present Ahaura Post Office (Former) building was constructed in 1894 following a fire in the previous building in 1893. Given that the population of Ahaura was recognised as being on the decline at that time, there was some questioning of whether a new post and telegraph office building was required. Some suggested that the post office could instead use an existing building owned by the National Bank. However, others in the community, eager for development in the town, wanted a new building and collected donations for a clock to go on it.

Constructed of rusticated weatherboards, the Ahaura Post Office (Former) is square in plan and has a corrugated steel hipped roof with deep eaves. Six timber brackets sit below the north-facing eaves. At the centre of the north façade is a round arch above which sits a circular clock. The archway leads to a recess with a sash window and, on the east side, a door. The archway is flanked on either side of the north elevation by a sash window. On the east elevation are three sash windows and a brick fire breast rising to a tall chimney at roof height. The west elevation has a door.

Shortly after the new building was completed, a small and short-lived gold rush brought a surge of optimism for Ahaura. Despite the down-sizing of the town, the post office continued to play an important role in communication until it was closed in 1991. Subsequently the building was converted to tearooms, and this involved extensive interior alteration. In 2014, the building operates as a craft gallery.