This austere Custom House, opened in 1884, housed Her Majesty’s Customs collectors who oversaw the collection of duties and taxes for the Customs Department. The Custom House has architectural significance as the building was designed by prominent Oamaru architectural partnership Forrester and Lemon; it also has historical and townscape significance as part of Oamaru’s Harbour/Tyne Street Historic Area.

Customs is the oldest government department in New Zealand, established in 1840, Its primary role was to collect revenue, particularly taxes on alcohol, tobacco, tea, sugar and grain. The Government appointed officials to monitor and administer customs matters at Ports of Entry such as Oamaru. Oamaru was declared a Port of Entry on 1 August 1861 and a ‘Warehousing Port’ for the purposes of the Customs Regulation Act in 1863. In January 1862 resident magistrate Thomas Windle Parker was appointed Sub-collector of Customs. In 1869, a Custom House Reserve was set aside. The Customs Department first used rooms at the Post and Telegraph Office, located an inconvenient distance from the port. As early as 1868, £2,500 was voted for a Custom House, but shortage of labour and other priorities delayed the call for tenders.

It was not until 1883 that building of the Custom House began. John Lemon, of Oamaru architectural partnership Forrester and Lemon, advertised for tenders in April 1883. Stone mason Alexander Watson won the tender. The North Otago Times described the Custom House, as a ‘two-storeyed building in the Italian style of architecture. The main entrance will be from Wansbeck street into a lobby 14ft by 8ft. The lobby communicates with a collector’s room on the right, 14ft by 17ft, and with a clerks’ room on the left, 14ft by 18ft; and leads through into a Long room, 21ft by 23ft – fitted with a spacious counter for the convenience of the public. To the left of the long room is a strong room, 12ft square, lavatory, etc. The upper storey is at present to remain unfinished. The building will be of a plain but substantial appearance, and will be of advantage to the town if only as filling up the vacant corner it is to occupy.’ Lemon advertised for tenders for fencing at the Custom House on 11 January 1884. The new building, with its main entrance facing Tyne Street, opened for business on 16 February 1884.

Architectural historian Conal McCarthy writes that the Custom House was designed with ‘decorative restraint’ in a standard format for buildings of this type. The design was ‘plainly Classical’ like other customs houses in Timaru, Dunedin, Melbourne and Sydney. McCarthy writes that the ‘severe Tuscan portico’ marking the Tyne Street entrance, gives the building ‘an air of serious purpose that matches its function’ and it appears to, in the words of another writer, ‘frown down on recalcitrant who might wish to avoid paying their dues.’

The Customs Department was not the only occupant of this building. For a time from the late 1880s until 1905, the Waitaki County Council had their offices there; after the council moved out the building was home to the newly formed Oamaru Technical School. The Technical School moved out in 1925. The Customs Department seems to have moved in and out of the building. During the 1930s, the Department of Agriculture and the Government Mens’ Employment Bureau moved in. In 1960 the land was set apart as a public reserve for ‘Buildings of the General Government. In 1966, Oamaru ceased to be a Port of Entry. The Custom House was sold to William Bee, who in 1972 sold the building to The Royal Antediluvian Order of Buffaloes. The New Zealand Historic Places Trust bought the building in 1981, and after restoring it, sold it to the North Otago Art Society Incorporated. In 2015, it remains home to the art society, providing a gallery and working space.