Cap badge Royal Tank regiment

At the outbreak of war, the regiment consisted of 20 battalions, 8 regular and 12 territorial.

• Regular Army
  • Heavy Armoured Brigade (Egypt): 1st RTR and 6th RTR
    
  • 1st Heavy Armoured Brigade: 2nd RTR, 3rd RTR and 5th RTR
    
  • 1st Army Tank Brigade: 4th RTR, 7th RTR and 8th RTR
    
• Territorial Army
  • 21st Army Tank Brigade: 42nd RTR, 44th RTR and 48th RTR
    
  • 23rd Army Tank Brigade: 40th RTR, 46th RTR and 50th RTR
  • 24th Army Tank Brigade: 41st RTR, 45th RTR and 47th RTR
  • 25th Army Tank Brigade: 43rd RTR, 49th RTR and 51st RTR
    

During the course of the war, four "hostilities-only" battalions were formed: the 9th, 10th, 11th and 12th. 11 RTR formed part of 79th Armoured Division (a specialist group operating vehicles known as "Hobart's Funnies"), initially equipped with "Canal Defence Light" tanks, it converted to "Buffalo" (the British service name for the US Landing Vehicle Tracked) not long after D-Day and participated in the assault crossing of the Rhine. Prime Minister Winston Churchill was ferried across the Rhine in a Buffalo from 'C' Squadron, 11RTR.

The Regiment's numerous units took part in countless battles in the Second World War, including the Battle of Dunkirk, El Alamein, Italian Campaign, Burma Campaign and D-Day landings of 6 June 1944. Field Marshal Sir Bernard Law Montgomery would frequently wear the regiment's beret, with his Field Marshal's badge sewn on next to the regimental cap badge, as it was more practical whilst travelling on a tank than either a formal peaked hat or the Australian slouch hat he previously wore