Correlated electron phenomena in lanthanide and actinide materials are driven by a complex interplay between the f and d orbitals. In this study, aluminum K-edge x-ray absorption spectroscopy and density functional theory calculations are used to evaluate the electronic structure of the dialuminides, MAl2 (M = Ce, Sm, Eu, Yb, Lu, U, and Pu). The results show how the energy and occupancy of the 4f or 5f orbitals impacts mixing of Al 3p character into the 5d or 6d conduction bands, which has implications for understanding the magnetic and structural properties of correlated electron systems