Three thiacalix[4]arene polynuclear complexes have been prepared by literature methods for detailed magnetic investigation. The [Fe3O(L)2] (LH4 = thiacalix[4]arene) complex is found to exhibit interesting anti-ferromagnetic exchange coupling. Jahn–Teller distortion in [Cu4(L)2] complex leads to strong anti-ferromagnetic coupling at low temperatures. The temperature-dependent susceptibility of the [(μ-H2O)Eu2(LH)2(DMF)4] complex is well described by a ground state involving the thermal population of the lowest three excited states.