The TO-55 was a modification of the T-55 fitted with a flamethrower, intended to assist infantry in pushing against enemy defensive positions during battle, while allowing for increased survivability of such a weapon system when compared to flamethrowers carried by infantry. The original tank turret was modified by incorporating an ATO-200 flamethrower coaxial with the main armament. The standard ammunition stowage in the bow next to the driver was modified to accommodate a flammable liquid tank with a capacity of 460 litres. The flamethrower was aimed by rotating the entire turret, and ignited by pyrotechnic charges. Instead of being manually controlled, the rate of fuel consumption was standard, averaging 36 litres per burst of flame. The flamethrower had a maximum effective range of about 200 metres and an initial muzzle velocity of about 100 meters per second.

Introduced in Update "Sons of Attila", the TO-55 resembles the standard T-55 variant in appearance, but its coaxial armament has been replaced by a flame projector. The flamethrower, while appealing, has a very limited range and is only useful for open/lightly armoured vehicles, making it a very situational armament. However, being built on the basis of the T-55, the TO-55 is a tried-and-true platform with dependable armour and adequate firepower, and can still shine in the right hands with good tactics and careful planning.

The TO-55 is much like the T-54 (1951) and T-55A sharing the same ammo. However, it is basically a better T-54 whilst being at the same BR. It can be considered as a direct upgrade, since the TO-55 is really just the T-55A with T-54 (1951) ammo. This brings some advantages compared to the T-54, for example, the T-55 series carries the D-10T2S compared to the T-54's D-10T. The biggest difference is that is has a two-plane stabilizer, giving it a good advantage when shooting on the move. It also has ESS capabilities and the 3D3 smoke shell, allowing it to confuse enemies or create a smokescreen. Another advantage it has is the V-55V diesel engine, which has more horsepower over the T-54's V-54 engine. The last difference is the addition of a NVD.

The only advantage the T-54 has over the TO-55 is a higher ammo capacity (34 > 25) and a larger ready rack (20 > 7) so keep in mind. However, with the potent D-10T2S cannon, ammo should not be too much of an issue. The flamethrower also replaces the PKT machine gun, but it is barely an issue.