The novel electric, magnetic and multiferroic properties of the metal formate perovskites have resulted in substantial scientific attention over the past fifteen years. Their bulk ground-state magnetic properties have been reported, but their magnetic excitations are less well understood; yet understanding these will be vital to modelling and tuning these materials’ useful magnetic behaviour. We have previously measured the magnetic inelastic spectrum of two materials in this family that contain dimethylammonium ions. We now propose an INS study of the analogous methylammonium compounds. These data will be of interest in their own right, especially because one target material is a known multiferroic; but they will also enable us to directly demonstrate the effects of replacing the organic cation, helping to establish a general understanding of the whole family’s magnetic properties.