Hailakandi district is one of the 33 districts of Assam state in north-eastern India. It makes up the Barak Valley alongside Cachar and Karimganj. It was constituted as a civil subdivision on 1 June 1869. Subsequently, it was upgraded to a district in 1989, when it was split from Cachar district.

The Barak Valley is the southernmost region and administrative division of the Indian state of Assam. It is named after the Barak river. The Barak valley consists of three administrative districts of Assam namely - Cachar, Karimganj, and Hailakandi. The main and largest city is Silchar, which seats the headquarter of Cachar district and also serves as administrative divisional office of Barak valley division. The valley is bordered by Mizoram and Tripura to the south, Bangladesh and Meghalaya to the west and Manipur to the east respectively. Once North Cachar Hills was a part of Cachar district which became a subdivision in 1951 and eventually a separate district. On 1 July 1983, Karimganj district was curved out from the eponymous subdivision of Cachar district. In 1989 the subdivision of Hailakandi was upgraded into Hailakandi district.