Analysis of the ancestry responses of the population in SSROC region in 2021 shows that the top five ancestries nominated were:
- English (385,308 people or 22.0%)
- Australian (340,153 people or 19.4%)
- Chinese (225,477 people or 12.9%)
- Irish (151,323 people or 8.6%)
- Scottish (102,819 people or 5.9%)
In combination these five ancestries account for 1,205,080 responses in total, or 68.69% of all responses.
The major differences between the ancestries of the population in SSROC region and Greater Sydney were:
- A larger percentage of people with Greek ancestry (4.9% compared to 2.4%)
- A larger percentage of people with Chinese ancestry (12.9% compared to 10.6%)
- A smaller percentage of people with Australian ancestry (19.4% compared to 22.3%)
- A smaller percentage of people with Indian ancestry (2.4% compared to 4.5%)