The complex [Na4((CH3)2CO)15][PtBi2I12]·3(CH3)2CO (1) has been prepared by the reaction of BiI3, NaI and H2[PtCl6]·6H2O and structurally characterized using X-ray diffractometry. It represents the first example of a polyiodobismuthate with an octahedral heterometallic unit. Interatomic interactions in the [PtBi2I12](2-) anion were characterized using the topological methods QTAIM and ELF.