Calderdale is a metropolitan borough in the metropolitan county of West Yorkshire, England, named after the River Calder. Administrative center is the city of Halifax. Other important towns in the district are Brighouse, Elland, Hebden Bridge, Heptonstall, Mytholmroyd, Queensbury, Ripponden, Sowerby Bridge and Todmorden. It is twinned with Aachen in Germany and Blatná in the Czech Republic.

The reorganization of the limits and the capabilities of local authorities led in 1974 to form the Metropolitan Borough. Were fused while the County Borough of Halifax, Brighouse and Todmorden the Boroughs, Urban Districts Elland, Hebden Royd, Ripponden and Sowerby Bridge, as well as a part of the Urban District Queensbury and Shelf. These authorities previously belonged to the county of West Riding of Yorkshire.

1986 Calderdale was in fact a Unitary Authority, as the central government dissolved the overall management of the county. Calderdale remained for ceremonial purposes part of West Yorkshire, as well as for individual higher-level tasks such as police, fire and public transport.