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Statistical Area 1 2023 update
SA1 2023 is the first major update of the geography since it was first created in 2018. The update is to ensure SA1s are relevant and meet criteria before each five-yearly population and dwelling census. SA1 2023 contains 3,251 new SA1s. Updates were made to reflect real world changes including new subdivisions and motorways, improve the delineation of urban rural and other statistical areas and to ensure they meet population criteria by reducing the number of SA1s with small or large populations.
Description
This dataset is the definitive version of the annually released statistical area 1 (SA1) boundaries as at 1 January 2023, as defined by Stats NZ. This version contains 33,164 SA1s (33,148 digitised and 16 with empty or null geometries (non-digitised).
SA1 is an output geography that allows the release of more low-level data than is available at the meshblock level. Built by joining meshblocks, SA1s have an ideal size range of 100–200 residents, and a maximum population of about 500. This is to minimise suppression of population data in multivariate statistics tables.
The SA1 should:
form a contiguous cluster of one or more meshblocks,
be either urban, rural, or water in character,
be small enough to:
- allow flexibility for aggregation to other statistical geographies,
- allow users to aggregate areas into their own defined communities of interest,
form a nested hierarchy with statistical output geographies and administrative boundaries. It must:
- be built from meshblocks,
- either define or aggregate to define SA2s, urban rural areas, territorial authorities, and regional councils.
SA1s generally have a population of 100–200 residents, with some exceptions:
- SA1s with nil or nominal resident populations are created to represent remote mainland areas, unpopulated islands, inland water, inlets, or oceanic areas.
- Some SA1s in remote rural areas and urban industrial or business areas have fewer than 100 residents.
- Some SA1s that contain apartment blocks, retirement villages, and large non-residential facilities (prisons, boarding schools, etc) have more than 500 residents.
SA1 numbering
SA1s are not named. SA1 codes have seven digits starting with a 7 and are numbered approximately north to south. Non-digitised codes start with 79.
As new SA1s are created, they are given the next available numeric code. If the composition of an SA1 changes through splitting or amalgamating different meshblocks, the SA1 is given a new code. The previous code no longer exists within that version and future versions of the SA1 classification.
Digitised and non-digitised SA1s
The digital geographic boundaries are defined and maintained by Stats NZ.
Aggregated from meshblocks, SA1s cover the land area of New Zealand, the water area to the 12-mile limit, the Chatham Islands, Kermadec Islands, sub-Antarctic islands, off-shore oil rigs, and Ross Dependency. The following 16 SA1s are held in non-digitised form.
7999901; New Zealand Economic Zone, 7999902; Oceanic Kermadec Islands,7999903; Kermadec Islands, 7999904; Oceanic Oil Rig Taranaki,7999905; Oceanic Campbell Island, 7999906; Campbell Island, 7999907; Oceanic Oil Rig Southland, 7999908; Oceanic Auckland Islands, 7999909; Auckland Islands, 7999910; Oceanic Bounty Islands, 7999911; Bounty Islands, 7999912; Oceanic Snares Islands, 7999913; Snares Islands, 7999914; Oceanic Antipodes Islands, 7999915; Antipodes Islands, 7999916; Ross Dependency.
For more information please refer to the Statistical standard for geographic areas 2023.
Generalised version
This generalised version has been simplified for rapid drawing and is designed for thematic or web mapping purposes.
Digital data
Digital boundary data became freely available on 1 July 2007.