Thornleigh, NSW
By Lauren McCaleb · Reviewed by Dylan Duncan ·
Among Australia's more advantaged suburbs
Thornleigh is more socio-economically advantaged than about 97% of the 14,462 Australian suburbs we score, based on the ABS SEIFA index (raw score 1122, where about 1000 is the national average).
A socio-economic measure from ABS Census data — not a measure of how good a suburb is to live in or visit. How we calculate this.
Thornleigh at a glance
- Population (2021)
- 8,898
- Median age
- 40
- Median weekly household income
- $2,681
- SEIFA score
- 1122
- Coordinates
- -33.7205, 151.0811
Thornleigh demographics (2021 Census)
The figures below profile Thornleigh using the Australian Bureau of Statistics 2021 Census; every percentage is a share of a clearly stated Census count, so each one traces back to the source. At a glance, the largest age group is mid-life (45–64) at 28%, 23% of homes are rented, and 37% of residents were born overseas.
Age profile
| Age group | People | Share |
|---|---|---|
| Children (0–14) | 1,864 | 21% |
| Youth (15–24) | 1,082 | 12% |
| Young adults (25–44) | 2,154 | 24% |
| Mid-life (45–64) | 2,472 | 28% |
| Seniors (65+) | 1,331 | 15% |
Share of the 8,903 people counted by age.
Housing and households
| Tenure | Dwellings | Share |
|---|---|---|
| Owned outright | 937 | 31% |
| Owned with a mortgage | 1,281 | 43% |
| Rented | 693 | 23% |
| Dwelling type | Dwellings | Share |
|---|---|---|
| Houses | 2,274 | 76% |
| Townhouses & semis | 462 | 16% |
| Flats & apartments | 237 | 8% |
Tenure and dwelling shares are of the roughly 2,976 occupied private dwellings in Thornleigh.
- Median weekly rent
- $530
- Median monthly mortgage
- $2,800
- Average household size
- 2.9 people
- Median weekly family income
- $3,016
- Median weekly personal income
- $1,025
Community and culture
- Born overseas
- 3,245 (37%)
- Speaks a language other than English at home
- 2,838 (33%)
- Aboriginal and/or Torres Strait Islander
- 54 (1%)
Work and education
- Completed Year 12
- 5,293 (80%)
- Labour-force participation
- 67%
- Unemployment rate
- 4.2%
- Employed full-time
- 2,772
- Employed part-time
- 1,348
Source: ABS Census of Population and Housing, 2021 (General Community Profile, by Suburb and Locality). © Australian Bureau of Statistics, released under CC BY 4.0. How we group bands and derive each share is set out on our methodology page.
Weather and climate in Thornleigh
Based on 2014–2023 records, the warmest month in Thornleigh is January (average daytime high around 28.4°C) and the coolest is July (around 16.8°C). The area receives roughly 854 mm of rain across the year.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 28.4°C | 18.6°C | 85 mm |
| Feb | 27.1°C | 18.1°C | 92 mm |
| Mar | 25.4°C | 16.9°C | 139 mm |
| Apr | 22.9°C | 13.6°C | 72 mm |
| May | 19.7°C | 10°C | 37 mm |
| Jun | 16.7°C | 8°C | 57 mm |
| Jul | 16.8°C | 7.1°C | 56 mm |
| Aug | 17.9°C | 7.6°C | 52 mm |
| Sep | 20.9°C | 9.8°C | 44 mm |
| Oct | 23.7°C | 12.6°C | 77 mm |
| Nov | 25.2°C | 14.7°C | 73 mm |
| Dec | 27.5°C | 16.9°C | 70 mm |
Climate normals, 2014–2023 (Open-Meteo, ERA5 reanalysis).
Common questions about Thornleigh
Where is Thornleigh?
Thornleigh is a suburb of New South Wales, Australia.
What is the population of Thornleigh?
At the 2021 Census, Thornleigh had a population of about 8,898.
Is Thornleigh an advantaged area?
Thornleigh has an ABS SEIFA score of 1122, where about 1000 is the national average — higher scores indicate greater relative socio-economic advantage. That gives it a Suburb Score of 97 out of 100 — more socio-economically advantaged than about 97% of Australian suburbs.
What is the weather like in Thornleigh?
Thornleigh has average daytime highs of about 22.7°C and overnight lows of about 12.8°C, with roughly 854 mm of rain across the year (based on 2014–2023 climate normals).
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