NSW Boundary Concordance

Four concordances have been calculated for NSW boundaries.

LGA_FederalElectoralDivision_concordance

The dataset shows the relationship between LGA boundaries and Federal Electoral Divisions. area_ratio attribute indicates the portion by area of the LGA within each Federal Electoral Division area (a value of 1 indicates the LGA is entirely within the given Federal Electoral Division). Likewise, population_ratio_2021 attribute indicates the portion by population of the LGA within each Federal Electoral Division area.

LGA_StateElectoralDistrict_concordance

The dataset shows the relationship between LGA boundaries and State Electoral Districts. area_ratio attribute indicates the portion by area of the LGA within each State Electoral District area (a value of 1 indicates the LGA is entirely within the given State Electoral District). Likewise, population_ratio_2021 attribute indicates the portion by population of the LGA within each State Electoral District area.

postcode_LGA_concordance

The dataset shows the relationship between postcodes and LGA boundaries. area_ratio attribute indicates the portion by area of the postcode within each LGA area (a value of 1 indicates the postcode is entirely within the given LGA). Likewise, population_ratio_2021 attribute indicates the portion by population of the postcode within each LGA area. Postcode boundary is not a standard Spatial Service dataset. It's been derived using suburb that is maintained by Spatial Service. The result is indicative. Where postcode and LGA boundaries do not match exactly, very small percentages might occur.

suburb_LGA_concordance

The dataset shows the relationship between suburbs and LGA boundaries. area_ratio attribute indicates the portion by area of the suburb within each LGA area (a value of 1 indicates the suburb is entirely within the given LGA). Likewise, population_ratio_2021 attribute indicates the portion by population of the suburb within each LGA area. A population_ratio_2021 total of 0 for a suburb indicates there is no population estimated in the suburb per the methodology used.

Caveats:

Spatial Service does not have access to official postcode boundary. It has been derived from ‘suburb’.
There are a lot of small areas. These are slithers. It can occur where boundaries overlap or do not align.
Due to rounding, ratios for a given location may not total 1.
Depending on the software engine, it is possible to get different results for the same operation.
Population and population ratios have been estimated from 2021 Census mesh block counts (Australian Bureau of Statistics). Population ratios are indicative only and will not reflect any developments nor population changes since August 2021.

Related resource

An excel table of Suburb and LGA percentage area split is available here: Suburb and LGA Percentage - Spatial Collaboration Portal

Metadata

Content Title	NSW Boundary Concordance
Content Type	Hosted Feature Layer
Description	The NSW Concordance datasets are a collection of selected boundaries and their spatial relationships to one another. Selected boundary concordances in this dataset include: Ratios of Suburbs in Local Government Areas Ratios of Postcodes in Local Government Areas Ratios of Local Government Areas in State Electoral Districts Ratios of Local Government Areas in Federal Electoral Divisions Ratios area calculated for areas and populations (indicative only). These can differ greatly and are appropriate for different applications. For example, the suburb of Aberdeen is split between Muswellbrook and Upper Hunter LGAs. The area ratios between the LGAs are 0.3888 / 0.6112 and the population ratios are 0.0133 / 0.9867, respectively. So, while a third of the suburb is physically located in Muswellbrook LGA, nearly the entire suburb population is in Upper Hunter LGA. Update frequencies vary for each dataset based on boundary changes and Census releases.
Initial Publication Date	20/01/2026
Data Currency	01/01/3000
Data Update Frequency	Other
Content Source	NSW Administrative Boundaries Theme and Australian Bureau of Statistics
File Type	ESRI File Geodatabase (*.gdb)
Attribution	© State of New South Wales (Spatial Services, a business unit of the Department of Customer Service NSW). For current information go to spatial.nsw.gov.au
Data Theme, Classification or Relationship to other Datasets
Accuracy
Spatial Reference System (dataset)	GDA2020
Spatial Reference System (web service)	EPSG:7844
WGS84 Equivalent To	GDA2020
Spatial Extent	Full State
Content Lineage	For additional information, please contact us via the Spatial Services Customer Hub
Data Classification	Unclassified
Data Access Policy	Open
Data Quality	For additional information, please contact us via the Spatial Services Customer Hub
Terms and Conditions	Creative Commons
Standard and Specification
Data Custodian	DCS Spatial Services 346 Panorama Ave Bathurst NSW 2795
Point of Contact	Please contact us via the Spatial Services Customer Hub
Data Aggregator	DCS Spatial Services 346 Panorama Ave Bathurst NSW 2795
Data Distributor	DCS Spatial Services 346 Panorama Ave Bathurst NSW 2795
Additional Supporting Information	attribute values for _partial_area and _total_area are measured in square km
TRIM Number