It is commonly found as the tetrahydrate Co(CH3CO2)2·4 H2O, abbreviated Co(OAc)2·4 H2O.

Like many other transition metal acetates, cobalt(II) acetate forms by the reaction of cobalt oxide or hydroxide and acetic acid: The tetrahydrate has been shown by X-ray crystallography to adopt an octahedral structure, the central cobalt centre being coordinated by four water molecules and two acetate ligands.

[1] The analogous nickel acetate is isostructural.

[3] Cobalt acetate is a precursor to various oil drying agents, catalysts that allow paints and varnishes to harden.

[4] Anhydrous cobalt acetate is a widely used source of cobalt in the synthesis of materials,[5] catalyst,[6] and complexes.