Cortical development relies on precise regulation of neural progenitor cell self-renewal, differentiation, and the generation of diverse neuronal subtypes that assemble into functional circuits. Epigenetic mechanisms — including DNA methylation, histone modifications, and chromatin remodeling — integrate intrinsic transcriptional programs with extrinsic cues to guide these processes. This review first examines how epigenetic regulation shapes neural progenitor cell fate, balancing proliferation with neuronal and glial differentiation. The focus then shifts to later stages of cortical development, highlighting epigenetic control of neuronal subtype specification, laminar identity, and circuit formation. Together, these insights illustrate how epigenetic mechanisms provide both stability and adaptability in cortical cell fate determination and how epigenetic disruption contributes to neurodevelopmental disorders.