With the outbreak of the COVID-19 pandemic, virtual education replaced face-to-face instruction. Despite the pressure it imposed on educational institutions, this shift provided a rare opportunity to view the mathematics curriculum from a different perspective—one in which digital technologies constitute an inseparable component. Accordingly, the revision of school and university mathematics curricula through their integration with digital technologies has become increasingly necessary. The present study was conducted as a systematic review with the aim of explicating blended learning in mathematics. The sources reviewed included upstream documents in Iran and studies on blended learning in mathematics published between 2010 and 2025. The findings revealed that, given the various components to be blended and the type and quality of their integration, there is no single definition of blended learning in mathematics; nevertheless, the shared interpretation accepted by the global mathematics education research community emphasizes the integration of online instruction and traditional/face-to-face instruction in blended learning. It can be concluded from the findings that understanding the nature of blended learning and how it is implemented can serve as a guide for educational policymaking and the revision of the mathematics curriculum.