About the Data

Data Sources

Every suburb page pulls from a small number of authoritative, freely licensed sources. Nothing is scraped from a commercial property portal and nothing is inferred from a web search. If a number appears on the page, it came from one of these:

• Australian Bureau of Statistics, 2021 Census of Population and Housing (CC BY 4.0). Population, age bands, household composition, country of birth, ancestry, language at home, median personal and household income, median rent and mortgage, employment and industry of work, and long-term health conditions. Counts are reported at the Suburb and Locality (SAL) geography.
• ABS Socio-Economic Indexes for Areas (SEIFA) 2021. The SEIFA IRSAD (Index of Relative Socio-economic Advantage and Disadvantage) score and its national decile are attached to each suburb. Deciles range from 1 (most disadvantaged 10 percent of Australia) to 10 (most advantaged 10 percent).
• Australian Statistical Geography Standard (ASGS) Edition 3, 2021. SA3, SA4, Greater Capital City Statistical Area, and Remoteness Area classifications used for the "area" and "region" browse hierarchy and for the metro, regional, remote, and very remote tiers.
• Australia Post postcode file. Postcode to suburb relationships. Many Australian suburbs share a postcode with neighbouring suburbs, so postcodes do not correspond one-to-one with a single place.
• Geoscience Australia place and LGA boundaries. Latitude, longitude, Local Government Area assignment, and distance from state capital.
• ACARA School Profiles, 2025 (Creative Commons). Primary, secondary, and combined school names, sectors, and ICSEA values where published.

Coverage and What a "Suburb" Means

The site has one page per SAL (Suburb and Locality) in the 2021 ABS geography, filtered to populated Australian localities. Total pages with Census data: 14,590. A small number of SALs are shells, coastal margins, rail corridors, or split islands with no residents reported in 2021, and those are excluded.

SAL is a Census-time boundary. It is close to, but not identical to, the State Suburb (SSC) that a state government gazettes or that appears on a property title. Boundaries occasionally shift between Census cycles when new estates are developed or old names are retired. Where a page shows zero residents for a named suburb you will recognise, it is almost always a SAL that covers only industrial land or public space and has no dwellings inside it.

Derived Fields

A few fields on each page are not direct from the Census and are worth explaining.

Remoteness Tier

Each suburb is classified as metro, regional, remote, or very remote using the ABS Remoteness Area assigned to its SAL centroid in the 2021 ASGS. Major Cities map to metro, Inner and Outer Regional collapse to regional, and Remote plus Very Remote keep their ABS labels. The tier drives which introductory sentence is generated and which state averages a suburb is benchmarked against.

Coastal Flag

A suburb is treated as coastal when its SAL centroid sits within roughly three kilometres of the Australian coastline using Geoscience Australia's simplified national coast polygon. This is a deliberately broad cut. A harbourside suburb one street back from the water reads as coastal in normal speech even if the title register does not use the word, and the three kilometre buffer picks up most of those cases. It will occasionally flag a riverfront inland suburb as coastal where a wide tidal estuary reaches inland. The flag is used to choose between two stylistic variants of the intro paragraph and has no effect on any numerical data on the page.

Nearest Suburbs

The "nearby suburbs" list on every page is computed geographically, not alphabetically. For each suburb the renderer finds the closest suburbs by great-circle (haversine) distance between SAL centroids. This replaces the older alphabetical ordering and means that a suburb on the south-east coast of NSW will not list a suburb on the west coast of WA as a neighbour simply because they happen to share the same first letter.

State Averages and Decile Placement

State-level comparison figures (for example "median household income vs NSW") are population-weighted means across all suburbs in that state, recomputed from the same 2021 Census records. They match ABS totals within rounding. The SEIFA decile badge on each page is the national IRSAD decile as published by the ABS, not a state-level rank.

When the Data Was Last Updated

The Census base layer is 2021 and will not change until the Bureau releases 2026 Census results (expected 2027). SEIFA 2021 is the current edition. ACARA school data is refreshed annually. Postcode and LGA boundary refreshes from Australia Post and Geoscience Australia roll through whenever a new edition is published, typically once a year.

Each individual suburb page carries a "last reviewed" date in the footer. That is the date the current build was produced and does not imply the underlying data changed on that date.

Known Limitations

A few deliberate trade-offs that are worth flagging:

• Census income is 2021 dollars. Median weekly rent of $450 in 2021 is not $450 in 2026. The page shows the Census figure as-reported and does not CPI-adjust, because the ABS itself does not publish adjusted Census income series. For current market rents, see real estate listings rather than a demographic profile.
• Suburb shares a postcode with others. When you search a postcode, you get every SAL that the postcode covers. The first listed is not always the largest; it is the SAL the address file happens to sort first.
• Small-population suppression. ABS applies randomisation to small cells to protect privacy. In very small localities, fields like "ancestry" or "religion" may show zeros or round numbers where the true count was one or two people.
• Coastal edge cases. The three kilometre coastal cut will occasionally disagree with how locals describe a place. A suburb four kilometres inland that everyone calls a beach suburb will not carry the coastal flag; a suburb on an inland tidal river might.
• SA3 and SA4 names are ABS constructs. "Sydney - City and Inner South" is a statistical area, not an address anyone uses. The browse hierarchy uses these because it is the only stable nested geography the ABS publishes; it is not intended to replace how people describe where they live.

Attribution and Licensing

ABS 2021 Census and SEIFA data are published under Creative Commons Attribution 4.0 International (CC BY 4.0). ACARA school profiles are published under CC BY-NC 4.0. Postcode data is sourced from Australia Post's public directory. Geographic boundaries are sourced from Geoscience Australia and the ABS ASGS.

RefDat Postcodes is not affiliated with the Australian Bureau of Statistics, Australia Post, ACARA, or any state or Commonwealth agency. The site is an independent data reference product.

Corrections

If you spot something that looks wrong, write to admin@refdat.com with the page URL and the specific field. Most of the common "that's not right" reports fall into one of three categories: a SAL boundary that does not match a common-use suburb name, a small-population cell that looks off because of ABS privacy randomisation, or an ACARA school record that has been retired or renamed. Where something is genuinely wrong in the underlying Census extract, RefDat cannot change the source, but the page can be rebuilt from the correct source.