The structures of aquadichlorobis(1H-imidazole)cobalt(II), [CoCl(2)(Him)(2)(H(2)O)(2)] (Him is 1H-imidazole, C(3)H(4)N(2)), (I), and aquadichlorobis(1H-imidazole)nickel(II), [NiCl(2)(Him)(2)(H(2)O)(2)], (II), are isomorphous and consist of monomers with inversion symmetry. The three monodentate ligands (imidazole, chlorine and aqua), together with their symmetry equivalents, define almost perfect octahedra. Hydrogen-bonding interactions via the imidazole and aqua H atoms lead to a three-dimensional network.