We report on the magnetic properties of [formula omitted] [formula omitted] Rh, Pt) solid solutions which form in the hexagonal ZrNiAl structure. We performed neutron diffraction and bulk magnetization studies. All three solid solutions exhibit long-range magnetic order at low temperatures. Bulk magnetization studies indicate a ferromagnetic ground state for [formula omitted] [formula omitted] and [formula omitted] below 42, 41, and 27 K, respectively. At 4.2 K, the spontaneous moment ranges from [formula omitted]-atom [formula omitted] to [formula omitted]-atom [formula omitted] Below [formula omitted] we find additional weak magnetic contributions in the neutron diffraction data, and our refinement is consistent with magnetic moments along the c axis. The magnitudes of the moments are in good agreement with the spontaneous moments determined from bulk studies. The results are discussed in terms of [formula omitted] hybridization, which is modified by changes in the d band occupation and preferential occupation of the transition metals within the lattice.