Twizel (/ˈtwaɪzəl/) is the largest town in the Mackenzie District, in the Canterbury Region of the South Island of New Zealand. The town was founded in 1968 to house construction workers on the Upper Waitaki Hydroelectric Scheme. Today, Twizel is a service and tourist town for visitors to the area. It has a resident population of 1,790 (June 2025); during the summer, holidaymakers nearly triple the town's population.

Nearby Lake Ruataniwha supports rowing, sailing and water skiing. Twizel is 37 km (29 minutes drive) east of Lake Ōhau village, 30 km (20 minutes drive) north of Omarama and 60 km (42 minutes drive) south of Lake Tekapo.

The present town was built in 1968 by the Ministry of Works and Development as a greenfields project to house workers constructing the Upper Waitaki hydroelectricity scheme. The name comes from the nearby Twizel River, in turn named for Twizel Bridge in Northumberland by John Turnbull Thomson, Chief Surveyor of Otago in the mid-19th century.

The Waitaki hydro scheme consisted of 50 kilometres (31 mi) of canals, two dams, and four powerhouses (Tekapo B, Ōhau A, B and C), and the formation of Lake Ruataniwha, producing 848 MW of electricity. At the height of the project in the 1970s, population peaked of around 6,000.

At the time when the construction of the Upper Waitaki hydroelectricity scheme peaked, roughly in 1976, there were 800 cabins for single people and 1,224 family homes in Twizel. These mostly belonged to the Ministry of Works and Development to house the 1,900 employees of the Upper Waitaki hydroelectricity scheme.

The town was laid out in a 'Scandinavian' fashion, featuring looping roads and pedestrian ways, making it usually far more direct to walk than use a car. Shops, school, and recreational parkland formed a hub in the centre of the town, around which the residential area were built. A previous version of this layout had been tried at Otematata. Accommodation was highly segregated: in addition to single men's quarters in the middle of town, there was a series of different houses available, with the smallest for workers, staff houses for teachers and professionals, and the largest for engineers and other high-status residents.

As the intention was for the town to revert to farmland, there were many temporary features. For example, instead of putting in kerbing, channels, and footpaths at the edge of the road, a single expanse of seal was contoured in a very flat 'W' shape: the seal was highest at the outer edge (footpath) and in the middle (centreline), with a lower area serving as a channel and delineation between the roadway and footpath. Likewise, most of the town's telephone local loop is strung above ground to save the task of burying and then removing the lines. Most houses were prefabricated, and intended to be portable. Some were brought from Otematata, and some were later moved to Clyde for the next hydroelectricity project.

Government ministers argued that the town was intended to be temporary and eventually demolished. The government ministers saw Twizel as a financial liability. In October 1981, 100 houses had been reserved with the intention to transport them to Aramoana in expectation that the proposed aluminium smelter would be built. Several overseas investors offered to buy the whole town and develop it for tourism. One such investor, had plans to turn it into a "Las Vegas style casino town".