Kalachinsky District (Russian: Калачинский райо́н) is an administrative[1] and municipal[4] district (raion), one of the thirty-two in Omsk Oblast, Russia.

The area of the district is 2,800 square kilometers (1,100 sq mi).

[7] Within the framework of administrative divisions, Kalachinsky District is one of the thirty-two in the oblast.

[1] The town of Kalachinsk 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.

[1] As a municipal division, the district is incorporated as Kalachinsky Municipal District, with the town of oblast significance of Kalachinsk being incorporated within it as Kalachinsk Urban Settlement.