The company was established in 1896 in Copenhagen by brass moulder Valdemar Nielsen under the name Vald. Nielsens Metalvarefabrik ("Vald. Nielsen's Metalworks"). Under the Nielsen family's ownership, the company developed steadily up to the end of the 1960s. Due to a lack of space, it was decided to move the factory to more modern premises in Haderslev. In 1969-70, a modern factory was built here, designed from the outset for industrial production. During this period, the Original NITO couplings started to account for an ever-increasing share of the company's turnover. Other innovative products from this period were NIF gas taps, OPAL showers and TOKANI drinking valves. In connection with an impending generational change in the early 1980s, the company was taken over by NKT A/S and then became a wholly owned subsidiary of A/S Fisker & Nielsen (Nilfisk Group). Under this ownership, the name was changed to Nitodan A/S in 1985. Thus, the company's name also came to reflect the main product. Today, the company's name is NITO A/S. As part of a change in strategy within the NKT Group, the company was sold in 2006 to Vikan A/S. From 1995 to 2006, the owners were various investors based in Southern Jutland. In 2018, Vikan A/S sold the company to CEO Martin Kragh, who to this day continues the work of carrying on the legacy and further developing NITO's reputation.