Banksia lies approximately 12 km south of the Sydney central business district and falls within the Bayside Council area, forming part of the St George region.
The suburb recorded a population of 3,277 at the 2021 census, showing a slight decline from 3,388 in 2016.
The median age in Banksia is 38 years, with the age group of 30–39 years most prevalent.
Approximately half of residents were born in Australia, and the community includes people with heritage from areas such as the former Yugoslavia, China, Lebanon, Greece and the Philippines.
English-only households account for around 40 per cent, with notable proportions speaking Macedonian, Arabic, Greek and Cantonese. Common religious affiliations include Catholicism, Eastern Orthodox, Islam and a significant share reporting no religion.
Public transport is anchored by Banksia railway station on the Illawarra line, located about 9.6 km from Central Station and serving approximately 2,000 daily passengers.
Buses—including the 420 route to Mascot and several NightRide services—supplement train connectivity.
Land use in Banksia is dominated by environmental living zones (around 57 per cent), followed by open space and low-density residential areas.
The suburb covers approximately 0.9 square kilometres and features five parks, which account for about 23 per cent of its area.
Owner‑occupation rates are steady at around 75 per cent, with most households comprising couples with children.
Median monthly mortgage repayments generally fall between $1,800 and $2,399, while median weekly rent stands at $600 for units and $800 for houses.
Commutes are diverse: about 8 per cent of adults use public transport, while 42 per cent travel by car and 34 per cent work from home.
The suburb supports a professional workforce, with many residents employed in occupations requiring tertiary qualifications.