The Bruce Highway forms most of the northern boundary of the locality, entering from the north-east (Isis River) and exiting to the north-west (Childers / Doolbi).[3]
Oaky Creek forms the southern boundary of the locality and becomes a tributary of the Sarahana Creek at the south-east of the locality. Sarahana Creek then forms the south-eastern boundary of the locality, becoming the Isis River.[3]
The terrain varies from 20 to 110 metres (66 to 361 ft) above sea level.[3]
The land use in the north of the locality is predominantly a mix of rural residential housing and crop growing (mostly sugarcane). There is cane tramway in the north of the locality to transport the harvested sugarcane to the Isis Central Sugar Mill. The land use in the south of the locality is predominantly grazing on native vegetation.[3]
In the 2016 census, South Isis had a population of 313 people.[6]
In the 2021 census, South Isis had a population of 381 people.[1]
Education
There are no schools in South Isis. The nearest government primary and secondary schools are Childers State School and Isis District State High School, both in neighbouring Childers to the north-west.[7]
