We analyze the stability of the non-heme water oxidation catalyst (WOC), Fe(bpmcn)Cl toward oxygen and illumination under nonaqueous and acidic conditions. Fe(bpmcn)Cl has been previously used as a C-H activation catalyst, a homogeneous WOC, and as a cocatalyst anchored to WO for photoelectrochemical water oxidation. This paper reports that the ligand dissociates at pH 1 with a rate constant k = 19.8(2) × 10 min, resulting in loss of catalytic activity. The combination of UV-vis experiments, H NMR spectroscopy, and cyclic voltammetry confirm free bpmcn and Fe present in solution under acidic conditions. Even under nonaqueous conditions, both oxygen and illumination together show slow oxidation of iron over the course of a few hours, consistent with forming an Fe-O intermediate as corroborated by resonance-enhanced Raman spectroscopy, with a rate constant of k = 3.03(8) × 10 min. This finding has implications in both the merits of non-heme iron complexes as WOCs as well as cocatalysts in photoelectrochemical schemes: the decomposition mechanisms may include both anchoring group hydrolysis and instability under illumination.