Kotlassky District was formed on June 25, 1924 and included areas of former Solvychegodsky and Velikoustyugsky Uyezds. In 1928, it was merged with Solvychegodsky District and in 1931, a part of Krasnoborsky District was appended to Kotlassky District. In the following years, the district remained in the same borders (with the exception of Solvychegodsky District, which was split out in 1938 and merged back in 1958), but the first-level administrative division of Russia kept changing. In 1929, Northern Dvina Governorate was merged into Northern Krai, which in 1936 was transformed into Northern Oblast. In 1937, Northern Oblast was split into Arkhangelsk Oblast and Vologda Oblast. Kotlassky District remained in Arkhangelsk Oblast ever since. Within the framework of administrative divisions, Kotlassky District is one of the twenty-one in the oblast. The town of Kotlas serves as its administrative center, despite being incorporated separately as a town of oblast significance—an administrative unit with the status equal to that of the districts. The district is divided into twelve selsoviets, one town of district significance (Solvychegodsk), and two urban-type settlements with jurisdictional territory (Privodino and Shipitsyno). Three other inhabited localities which previously had work settlement status were downgraded to rural status in 2005; these are Cheryomushsky, Kharitonovo, and Udimsky. The following selsoviets have been established (the administrative centers are given in parentheses):  As a municipal division, the district is incorporated as Kotlassky Municipal District. The town of oblast significance of Kotlas is incorporated separately from the district as Kotlas Urban Okrug. The municipal district is divided into three urban settlements and one rural settlement (the administrative centers are given in parentheses):  In 2010, timber industry accounted for 90.3% of the total industrial output of the district. In 2010, there were ninety-six farms in the district, producing meat (beef and pork), milk, cereals, and potatoes. Kotlas is an important railway hub, where the railway to Kirov branches off southeast from the main railway, connecting Konosha and Vorkuta (in the Komi Republic). The Northern Dvina and the Vychegda Rivers are navigable; there is regular passenger navigation on the Vychegda.