East Kalimantan (Indonesian:  Kalimantan Timur), is a province of Indonesia. Its territory comprises the eastern portion of Borneo. It has a population of about 3.5 million, and its capital is Samarinda.

East Kalimantan has a total area of 129,066.64 square kilometres (49,832.91 sq mi) and is the second least densely populated province in Kalimantan. The majority of the region shares a maritime border to the east with West Sulawesi and North Sulawesi; its coastline faces the Makassar Strait and the Celebes Sea. Its former northernmost region is now North Kalimantan; to its south, East Kalimantan borders the South Kalimantan province. The province bordered Sabah before the split, but still borders Sarawak.