This paper describes the synthesis, structure and spectroscopic and magnetic properties of two (μ-phenoxo)(μ-hydroxo)dicopper(II) complexes (1 and 2) which contain similar N,O-donor atoms but with distinct coordination arrangements around the Cu(II) centers. Structural and magnetic studies of 1 and 2 allowed us to evaluate, for the first time, the individual contributions of the {Cu(μ-phenoxo)Cu} and {Cu(μ-hydroxo)Cu} structural units to the antiferromagnetic coupling between the Cu(II) centers in these complexes.