In the mononuclear title compound, [Co(C(8)H(7)O(3))(2)(C(6)H(6)N(2)O)(2)(H(2)O)(2)]center dot 2H(2)O, the CoII ion is located on a crystallographic inversion center. The asymmetric unit is completed by one 4-methoxybenzoate anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water molecule. All ligands act in a monodentate mode. The four O atoms in the equatorial plane around the CoII ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two pyridine N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxylate group and the attached benzene ring is 6.47 (7)degrees, while the pyridine and benzene rings are oriented at a dihedral angle of 72.80 (4)degrees. An O-H...O hydrogen bond links the uncoordinated water molecule to one of the carboxylate groups. In the crystal structure, intermolecular O-H...O, N-H...O and C-H...O hydrogen bonds link the molecules into a three-dimensional network.