Erected by the Northern Steamship Company in 1898, this harbourside structure is an important reminder of Auckland's maritime past, and the role of shipping in the economic and social development of the region. Situated in a prime position between the wharves and the 1880s railway station, the building was constructed as offices for the Northern Company after it had become one of the leading inland-shipping businesses in northern New Zealand. The firm had been founded in Auckland in 1881 as an amalgamation of several smaller concerns, and ran freight and passenger services in the upper half of the North Island. Along with the Holm Shipping Company, it was one of only two major independent shipping companies in New Zealand by the early twentieth century, and later extended its services throughout the country before ceasing to trade in 1974.

The building was originally two storeys, having an ornate facade on its seaward side emblazoned with the company name. Like the nearby Colonial Sugar Refining Company Building (see 'Wharf Police Building'), it contained offices and storage, the latter being used for freight in transit. The storage area was reached through a cart passage towards one side of the building, while the remainder of the facade was symmetrical. Constructed of brick, the building was reorganised as business fortunes altered. An extra storey was added in the prosperous 1920s, using a similar style, while internal alterations were made as offices were let during the company's post-war decline. Following the winding up of the Northern Company in the 1970s, the interior was largely gutted and modifications were made to the western wall, which required strengthening after an adjacent building was demolished.

The Northern Steamship Company Building is one of the few nineteenth-century wharfside structures to survive in central Auckland, and reflects the city's role as a major port at the end of the colonial period. It is of national and regional importance for its links with the Northern Steamship Company, which was instrumental in the kauri gum, timber, farming and early tourism industries, and also provided social contact between coastal communities. The building is a visible reminder of the time when the wharfside area was a hub of maritime activity and makes a significant contribution to the historical fabric and appearance of the waterfront. Its value is enhanced by its proximity to related historical buildings, particularly the adjacent Union Fish Company building, which was used to repair Northern Company vessels, and is an important part of the Quay Street Historic Area.