The Baluchistan States Union or Balochistan States Union (BSU) was an administrative division of Pakistan that existed between 3 October 1952 and 14 October 1955 in the southwestern part of West Pakistan. It was formed by the four princely states of Kalat, Kharan, Las Bela and Makran with the capital at the town of Kalat. The area of the Union was roughly the south-western half of the modern province of Balochistan. The Union was separate from the Chief Commissioners Province of Baluchistan which comprised areas to the northeast of the Union. The Union did not include the enclave of Gwadar which was part of the Muscat and Oman. The four state rulers continued in office and retained autonomy.