The province of Carbonia-Iglesias (Italian: provincia di Carbonia-Iglesias; Sardinian: provìntzia de Carbònia-Igrèsias) was a province in the autonomous region of Sardinia, Italy. It included the historical area of Sulcis-Iglesiente and it was the smallest province of Sardinia. It is bordered by the provinces of Cagliari and Medio Campidano. All three provinces (Carbonia-Iglesias, Cagliari and Medio Campidano) were suppressed by the regional decree in 2016, integrated into the province of South Sardinia before being disestablished in 2025.
As of 2015, it has a population of 127,857 inhabitants over an area of 1,499.71 square kilometres (579.04Â mi), giving it a population density of 85.25 people per square kilometer. The provincial president was Salvatore Cherchi. It had two provincial capitals, Carbonia and Iglesias, with populations of 29,007 and 27,332 as of 2015, respectively.