This study, drawing on date from the Programme for International Student Assessment (PISA) 2009, examined the relationships of out-of-school-time mathematics lessons to mathematical literacy in Singapore and Australia. Results of two-level hierarchical linear modelling (HLM) analyses revealed that out-of-school-time enrichment lessons in mathematics were not significantly associated with mathematical literacy in Singapore and Australia. Out-of-school-time remedial lessons in mathematics were negatively associated with mathematical literacy in Australia, while such remedial lessons in mathematics were not significantly related to mathematical literacy in Singapore. Learning time in out-of-school-time lessons in mathematics was significantly negatively linked to mathematical literacy in Singapore and Australia. Implications of the findings are discussed.