This study examines how access to the academic curriculum creates patterns of inequality in Australian schools. Examining students' access to the academic curriculum gives an indication of how schooling is structured to support students in pursuing higher education opportunities. To date, little research attention has been given to the opportunities schools offer students to access the academic curriculum in order to enter university. Using administrative data on students and schools, we find that there are fewer average curriculum subjects, and less complexity in the subjects offered, in schools with low levels of socio-educational advantage. We argue that curriculum differentiation across schools is a systemic constraint that students in schools with higher levels of socio-educational disadvantage face in progressing to university because these schools are less able to provide students with access to core academic curriculum subjects in the final year of secondary school. Previous research has highlighted the social differences reflected in both educational access and outcomes due to the marketisation of schools and policies of school choice. Our findings indeed demonstrate that there are relationships between access to the academic curriculum, school socio-educational advantage and the social composition of schools, and these factors have important educational policy implications.