The first Yarra Junction Post Office and Dwelling have high level significance as rare surviving inter-war and earlier Post Office buildings, which may be the earliest such buildings in Yarra Ranges Shire. A popular meeting place for at least a century, the old Post Office had associations with the Paul family, district pioneers, and Cumming Smith and Co., a firm which successfully extracted chemicals from wood from 1907 to 1922, The Yarra Junction Post Office and Dwelling are important township buildings and local landmarks.

Yarra Junction retains both its original post office (now Wit and Wisdom Books) and the second post office which continues to serve this function. Both buildings are located on the north side of the Warburton Highway, and are separated by several other shops. This citation covers both properties.

The present Yarra Junction post office is a small timber building located in the main street of Yarra Junction. It occupies a landmark location at the intersection of the Warburton Hwy and the Yarra Junction-Noojee Rd. The property combines the post office and a residence.

From the street, the gable-roofed section of the post office is visible. It is a weatherboard-clad building with a cantilevered verandah extending along the main façade and across a small addition to the east. The façade was previously a combination of weatherboard on the lower section and cement sheet in the gable end, and the present owners have reclad the gable end in weatherboards but have left the louvred vent in-situ.

There are two main entry doors to the post office, the staff entry and the customers' entry. There are several small windows and a large bank of private post boxes. To the rear is the dwelling, which is a continuation of the same building. The house has been extended but retains the character of a 1920s or earlier building. One small section appears to have been built of pit-sawn boards.

Photographs of the building held by the present owners show the Wattle Refreshment Rooms as having a front parapet wall in timber, which largely covers the gable. A 1935 photograph shows the gabled façade much as it survives at present. An early photo (1913) shows a post supported verandah and a similar parapet to the 1935 photograph. It appears that the post-supported verandah has long been gone from this building.

The original post office is now Wit and Wisdom Books. It was not inspected during field work phase of the study, although it was noted as a building worthy of further investigation. The historical research subsequently revealed it to be the original post office. Wit and Wisdom Books is a timber building with two distinct sections. The larger section retains shopfront windows, a simple parapet and post-supported verandah. The shopfront is not original, and the earlier detailing has not been researched. The smaller section is set back from the street line. It once had a small verandah. This is now enclosed. Both sections have a gable roof.

Physical Conditions: Good

Integrity: Evidence of stages