The structure of bis(1,10-phenanthroline-kappa(2)N,N')(thiosulfato-kappa(2)O:S)manganese(II) methanol solvate, [Mn(S(2)O(3))(C(12)H(8)N(2))(2)].CH(3)OH, is made up of Mn(2+) centers coordinated to two bidentate phenanthroline (phen) groups and an S,O-chelating thiosulfate anion, forming monomeric entities. The structure of catena-poly[[diaqua(2,9-dimethyl-1,10-phenanthroline-kappa(2)N,N')manganese(II)]-mu-thiosulfato-kappa(2)O:S], [Mn(S(2)O(3))(C(14)H(12)N(2))(H(2)O)(2)](n), is polymeric, consisting of Mn(dmph)(H(2)O)(2) units (dmph is 2,9-dimethyl-1,10-phenanthroline) linked by thiosulfate anions acting in an S,O-chelating manner.