During World War II conversion to armour was started and the nine Mounted Rifle units were redesignated as Light Armoured Fighting Vehicles Regiment in the New Zealand Armoured Corps (NZAC). They were numbered after the most senior regiment in their lineage (thus leaving gaps in the numbering) and their erstwhile names were added as secondary titles.
In 1944 they were concentrated into three Armoured Regiments,
In 1947 The NZAC was made "Royal" (RNZAC).