M3A2 - Welded hull version of baseline M3. Only 12 produced, 10 of which were completed as Grant I.
M3A3 (Lee V) - Diesel-engined variant with welded hull. Side doors welded shut or later eliminated. 288 built, 49 supplied to the UK and 77 supplied to Brazil.
M3A4 - 109 built. Only used for training in the US.
M3A5 - Rivetted hull but otherwise as per M3A3. 591 built, 387 as Grant II. 23 supplied to Brazil.
Grant I - M3 and M3A2 with turret to British specification and internal differences, no cupola. 1,211 M3-based and 10 M3A2-based Grant Is supplied.
Grant II - M3A3 and M3A5. 381 Grant IIs based on M3A5 were supplied along with 83 based on M3A3.
Grant CDL - "Canal Defence Light"; based on M3 & M3A1 cast hull, 37mm turret replaced by one with a powerful carbon arc light which could be set to flicker rapidly to disorient the enemy. A BESA (UK) or Browning M1919 (US) machine gun was fitted and some were fitted with a dummy 37mm gun. The Grant CDL replaced the earlier Matilda II CDL in anticipation of use in North West Europe. 335 were converted in the UK, 497 M3A1CDL was used to by the US.