Mesh Blocks

Mesh Blocks (MB) are the smallest geographic areas defined by the ABS and form the building blocks for larger geographies in the ASGS. They broadly identify land use such as residential, commercial, primary production and parkland.

Statistical Areas Level 1 (SA1) are generally the smallest geographic areas used to release Census of Population and Housing data. Only total usual resident population and dwelling counts are released at the Mesh Block level.

ASGS Edition 4 contains 374,917 Mesh Blocks covering the whole of Australia without gaps or overlaps. This includes 114 non-spatial special purpose codes representing populations that are difficult to define geographically such as people in transit or have no fixed address. Migratory and No Usual Address are examples of this type of Mesh Block.

The Non ABS Structures are Mesh Block approximations of Local Government Areas, State Electoral Divisions, Commonwealth Electoral Divisions, Postal Areas, Suburbs and Localities, and Destination Zones.

As Mesh Blocks are very small, they can be aggregated to accurately approximate a large range of other geographies.

Mesh Blocks are designed according to established criteria first developed for ASGS Edition 1 (2011). The criteria are listed below in approximate order of importance, though the order of importance for some criteria may change depending on whether an area is urban or rural. For example, in urban areas, dwelling counts over 30 takes precedence over the requirement to match locality boundaries. In rural areas, matching locality boundaries sometimes takes precedence over minimum dwelling requirements because of the flow on effect Mesh Block design has on other structures in the ASGS. 

Mesh Blocks reflect dominant land use where possible. For example, residential areas are separated from commercial or industrial areas. Each Mesh Block also aims to reflect a single land use, for example parkland, but this is not always possible.

Land use is reflected in the Mesh Block category attribute according to the criteria in the table below.

Mesh Blocks are designed, where possible to contain between 30 and 60 dwellings, with some low dwelling count Mesh Blocks permitted to accommodate other design criteria. The minimum dwelling count of Mesh Blocks is designed to be small enough to aggregate accurately to a wide range of geographies and enables comparison of statistics between geographies. The Mesh Block target size helps to protect against the disclosure of confidential information.

Mesh Blocks follow road centrelines where possible. Roads, particularly major roads such as highways and motorways, are used as Mesh Block boundaries.

Zero Mesh Blocks are designed to capture areas with no population, such as airports, commercial or industrial developments, and large shopping complexes.

Mesh Blocks are designed in anticipation of development likely to occur before the 2026 Census of Population and Housing.

Where practical, Mesh Block boundaries do not cross cadastral (property) boundaries. Mesh Blocks are designed to be an aggregation of land parcels.

Each Mesh Block is a single area, for example every island is a single Mesh Block.

Where possible, Mesh Blocks are designed to contain or aggregate to whole officially recognised suburbs or localities that are defined by state and territory governments, especially in rural areas.

Mesh Blocks, where possible, contain an entire major facility. This includes hospitals, universities, airports, correctional centres, and retirement villages, which occupy a large area of land, extend across both sides of a street, or have an internal road network.

High density housing, such as apartment blocks, are identified and included in individual Mesh Blocks of compact shape, where possible. This means some Mesh Blocks have more than 60 dwellings.

Mesh Blocks aim to group communities of interest together wherever possible. For example, a whole apartment building, residential complex, parking lot, shopping complex, or retirement village is contained in one Mesh Block.

In urban areas, Mesh Blocks reflect town blocks where possible.

Where possible, all dwellings and buildings are accessible by road or pathway from within the Mesh Block so that communities of interest are grouped together. For example, the houses on a cul-de-sac are contained in one Mesh Block and therefore boundaries may follow the back fence line of a property boundary.

Where practical, Mesh Blocks are designed to be compact in size and shape, especially in urban areas.

Natural and constructed barriers, such as main roads, are used as boundaries to keep communities together. When a Mesh Block boundary follows a main road, adjacent Mesh Block boundaries follow the same road to provide consistency and continuity when Mesh Blocks are aggregated.

Mesh Block boundaries reflect topographic, or landscape features where practical including:

• water bodies such as rivers and lakes
• transportation such as roads and rail
• open space such as parkland, nature reserves and forests
• major mountain ranges or escarpments.

Mesh Blocks are not named. 

The 11-digit Mesh Block code comprises: A State and Territory identifier (1 digit), and a Mesh Block identifier (10 digits).

Some Mesh Blocks were redesigned for ASGS Edition 4. This ensures they continue to meet the design criteria and reflect growth and change in Australia's population, economy and infrastructure since the last edition of the ASGS in 2021.

Boundaries were modified as simply as possible to support comparison over time while also maintaining long term stability.

These changes have affected Mesh Block codes. For example, when a 2021 Mesh Block has been split or significantly redesigned, the original code is retired and a new, previously unused code is assigned for ASGS Edition 4.

Some boundary adjustments reflect changes to physical infrastructure, such as reclaimed land along the coastline and do not significantly alter the number of households, businesses, or land area within a Mesh Block. These changes are made for cartographic purposes to ensure ASGS boundaries align with standard mapping data. They are not considered significant and do not result in code changes.