Public transport (PT) has become importance in the travel task in Australian cities. Raising PT fares create a competitive disadvantage against private motor vehicle that are threatening the PT ridership. This paper seeks to gain further insights into transport vulnerability by exploring spatial patterns of household expenditure on PT fares and vehicle fuel in Brisbane metropolitan area. Through an analysis of household travel patterns and transport costs associated with the PT fares and private vehicles, this paper identified household commuting expenditures. The results show that across all suburbs, PT was not a cost-effective means of transport for households compared with private motor vehicle. The paper then compares the combined household trip costs with patterns of suburban socio-economic disadvantage in Brisbane, we demonstrate that the high PT fares exacerbates household exposure to higher transport costs, and compounds other forms of transport disadvantage and vulnerability. Keywords: Transport Disadvantage, Public Transport Fare, Vehicle Fuel Efficiency, Journey to Work, Spatial Analysis