During the First World War, Machine Gun Companies were developed both as independent units and later as components of Machine Gun Battalions. In the Second World War a Medium Machine Gun Company was either a sub-unit component of a Machine Gun Battalion attached to an infantry division, or an independent company belonging to an armoured division.

MMG Company - Infantry Division

The MMG Companies of Machine Gun Battalions in Infantry Divisions were composed of 3 platoons, each armed with 4 Vickers Guns.

Independent MMG Company - Armoured Division

Both overseas armoured divisions had an independent Machine Gun Company to provide fire support for the infantry brigade.

The company was slightly different than the one found in infantry divisional MG Battalions.

Company Headquarters
- Mortar Platoon (4 x 4.2" Mortars)
- MMG Platoon (4 x Vickers Gun
- MMG Platoon (as above)
- MMG Platoon (as above)
- Flamethrower Platoon (6 x WASP Carriers)

4th Canadian (Armoured Division)

The independent MG company for this division was the 10th Canadian Machine Gun Company (The New Brunswick Rangers).

5th Canadian (Armoured Division)

The independent MG company for this division was the 11th Canadian Machine Gun Company (Princess Louise's Fusiliers). When the division expanded to two infantry brigades in 1944, an additional Machine Gun Company was added, designated 12th Independent Machine Gun Company (Princess Louise's Fusiliers).