Picton is a relatively late Troup Vintage station. The building is capped with Marseilles tiles with ridge cresting, and clad with rusticated weatherboards. There is a verandah with corrugated-iron roof on the platform elevation, and its railway-iron supports are capped with ornamental wrought-iron hoops. On the road elevation the station entrances are defined by open porches, with gables behind echoing their form. Some of the station's original decoration, in particular the half-timbering, has been removed. The interior has been much altered from the original to the extent that little railway flavour remains.
Picton's first station was erected in 1874 when the port was becoming an important conduit for freight traffic - the original platform is still behind the museum on London Quay. When this building was replaced a new wharf was also constructed, as the two operations were so closely linked. The wharf was finished in December 1913, and both the wharf and the new station were officially opened on 10 February 1914. It was estimated in 1912 that the station would cost £1620. Picton was Marlborough's busiest port, and traffic increased sharply after 1962 when the Wellington-Picton rail ferry began operating. As this service expanded, major additions to the railway yard were needed in the 1970s and 1980s. The station was the terminus for express train and railcar services linking Marlborough and Canterbury, and now for the TranzCoastal express, introduced in 1989 as the Coastal Pacific. Rail operations formerly based at the station are now sited at the ferry terminal. The station building was proposed for replacement in 1974 but only the main office was upgraded. In 1981 $17,000-worth of alterations, including a separate office for the stationmaster and a rearrangement of the counter area, were provided. In 1986 Picton closed to less-than-wagonload freight: its roles are now as a passenger terminal and for the inter-island freight operation.