Statistical area level 2 (SA2) code N(9) ASGS ed.3

There are 2,473 SA2 regions covering the whole of Australia without gaps or overlaps. These include 19 non-spatial special purpose codes, representing populations that are difficult to define geographically such as people who are in transit or have no fixed address. These are represented by Migratory – Offshore – Shipping and No Usual Address SA2s.

SA2s are designed using multiple criteria, listed below in approximate order of importance.

Population
SA2s generally have a population between 3,000 and 25,000 with an average of about 10,000 people. SA2s in remote and regional areas generally have smaller populations than those in urban areas. There are some SA2s outside these target population ranges due to other considerations including:

• The relative sparseness of the population in remote regions (an SA2 with a population of 3,000 may cover too large and diverse a geographic area to be meaningful).
• The benefit of preserving recognisable areas for which there is a considerable amount of historical data.
• Isolated geographic areas, such as islands or other isolated populations.
• The need to avoid subdivisions of otherwise coherent regions, such as very large suburbs or regional towns.

Functional areas
A functional area is the area from which people come to access services at a centre. This centre may be a rural town, a regional city, a commercial and transport hub within a major city, or the major city itself. The concept of a functional area is used at all levels of the ABS Main Structure and is particularly essential to the design of SA2s outside of major urban areas.
A centre and its functional area are represented by one or more SA2s. A rural town and its functional area may be combined into a single SA2. A larger town may be identified by a single SA2 and its functional area around the town by a second SA2. Larger towns and regional cities may be represented by several SA2s.

Growth
SA2s containing regional towns or on the fringes of larger cities are designed to contain the urban area, any immediately associated semi urban development, and likely growth areas in the next 10 to 20 years. This is to ensure that the SA2 boundaries remain stable over several population and housing censuses.

Suburbs and Localities (or rural suburbs)
Where possible, SA2s consist of whole gazetted suburbs or rural localities. This is to make the regions as meaningful as possible to users unfamiliar with statistical geography and to facilitate address coding to other ASGS units.
In regional and remote areas, gazetted localities are usually too small to be represented by a single SA2 and are combined with neighbouring areas to represent a functional area or other meaningful region.

In major cities, SA2s often represent single suburbs. Suburb size is variable within and between cities and they do not always make a convenient region to be used directly as an SA2. Where this occurs, five general criteria are used to cluster smaller suburbs together or break up extremely large suburbs:

• shared road networks
• shared community facilities
• Local Government Areas
• shared historical or social links
• socio-economic similarity

Local Government Areas
Local Government Areas (LGAs) are considered in the design of SA2s and are often adopted where the LGA boundary satisfies one or more of the following:

• it closely aligns with gazetted suburb boundaries
• it reflects the underlying settlement pattern
• it represents the functional area of a regional town or city
• it has a high degree of recognition among stakeholders
• it aligns to a significant recognisable geographic feature

Zero SA2s
Zero SA2s have a nil population. They are created to represent large unpopulated areas that are not easily combined with surrounding populated SA2s.
They may include:

• major infrastructure (such as ports and airports)
• significant bodies of water
• major commercial and industrial zones
• national parks
• defence land
• very large urban parks
• very large sporting precincts

SA2 coding structure:

Australian Bureau of Statistics (Jul2021-Jun2026), Australian Statistical Geography Standard (ASGS) Edition 3, ABS Website, accessed 5 September 2024.