The 2S3M ("Akatsiya") was a modernized version of the 2S3 self-propelled artillery. As the first of three modernization attempts, it featured a new 2A33 howitzer capable of loading more advanced ammunition, increasing its effective range, reliability, and accuracy. The 2S3M also incorporated a single mechanized ammunition rack, as opposed to the 2S3's two. This change allowed for an increase in the maximum ammunition capacity from 40 to 46 rounds. Even though the changes weren't significant, they were seen as a step in the right direction toward bringing Soviet artillery efficiency more in line with that of western nations. The 2S3M served as the main production model of the series and was widely deployed in the Soviet Union and its allies. Further efforts to extend the service life of the series were undertaken in the mid-1980s and early 2000s, resulting in the 2S3M1 and 2SM2 variants, respectively.

The 2S3M was introduced in Update "Winged Lions". In comparison to the SU tank destroyer series, it offers significantly different gameplay. Other than the obvious difference of not being a "casemate", it is very lightly armoured but highly mobile. Its cannon relies on the use of HE and HE-VT shells capable of disintegrating even the most heavily armoured tanks at its battle rating. The proxy shells are also sufficient against low flying aircraft, as they have a very capable fuse and a high explosive effect that can cause significant damage.