The most common industries of employment for persons aged 15 years and over usually resident in St Marys were Road Freight Transport 5.1%, Supermarket and Grocery Stores 3.1%, Cafes, Restaurants and Takeaway Food Services 2.9%, School Education 2.5% and Hospitals 2.3%.

There were 6,354 families in St Marys: 43.1% were couple families with children, 29.5% were couple families without children, 25.5% were one parent families and 1.9% were other families.

English was stated as the only language spoken at home by 72.2% of persons usually resident in St Marys. The most common languages other than English spoken at home were: Arabic 2.8%, Greek 1.4%, Croatian 1.4%, Hindi 1.4% and Samoan 1.1%.

* statistcs taken from the 2006 Census for postal area 2760 conducted by the Australian Bureau of Statistics