The IS-2M was a Soviet postwar modernization of the IS-2 tank, designed to extend its service life during peacetime. In the 1950s, the IS-2 still constituted a significant portion of the Soviet Army’s combat strength; however, many of its components had become obsolete or were worn out by that point. Therefore, in 1957, a major overhaul and modernization of all in-service tanks began. Specifically, the tanks were fitted with a new engine and transmission; their ammunition load was increased to 35 shells; the driver was equipped with a periscope instead of a triplex sight; the turret design was modified; the gun elevation mechanism was replaced; and a new radio was installed. There were also a number of other, less significant changes. Beginning in the 1960s, the tanks were transferred to the Soviet Army’s reserve, and a number of vehicles were sent to Cuba, North Korea, and Czechoslovakia. Russia completely withdrew the tanks from its reserve in 1993, but Cuba continues to use them as pillboxes.

The IS-2M (Be Prepared!) was introduced in Update 2.59 "Sky Odyssey". In battle, the modified IS-2 is virtually identical to its predecessor. It is a tank with a powerful 122mm gun and heavy armor. However, it has an extremely long reload time, and its mobility leaves much to be desired.