A five digit code which is assigned alphabetically to each locality within each State. The code list used for allocation of locality codes to CD's is based on an updated version of the 1966 locality tabulation. Initially in 1966, codes started at 00010 for the first locality in each state and progressed, in tens i.e. 00010, 00020, 00030, etc.
For the 1971 Census, and subsequently for the 1976 Census, localities that had to be added were given intermediate codes e.g. 0001 S where only one was inserted and 00013, 00015, 00017 etc. where more than one was inserted. The aim was to leave sufficient space in the code list to allow more codes to be inserted at subsequent censuses while maintaining a consistent alphabetical code within each state. Codes are allocated to CD's only in cases where the CD comprises one bounded locality of more than 200 population in its entirety, or where the complete CD comprises part of a bounded locality of more than 200 population. In cases where a CD has more than one locality within its boundaries, as in rural areas, a locality code of 0 is given to the CD.
Migratory CD's in all states are given a locality code of 99999.