The structure of bis(cobaltocenium) tetrachloridocobaltate(II) dichloromethane 1.2-solvate, [Co(C5H5)2]2[CoCl4]·1.2CH2Cl2, has been determined at 100 K. The title compound crystallizes in the space group P\overline{1} and is an example of an unusual Z′ = 5 structure. The asymmetric unit contains ten cobaltocenium ions, five tetrachloridocobaltate(II) ions and six molecules of dichloromethane, i.e. 5{[Cp2Co]2[CoCl4]}·6CH2Cl2. All the cobaltocenium ions are determined to be in the eclipsed conformation with respect to the cyclopentadienyl rings.