We have reported a mononuclear iron(II) complex based on a macrocyclic tetradentate ligand along with a bidentate coligand and explored the spin-state switching in the prepared iron(II) complex by temperature-dependent single crystal analyses, magnetic, photomagnetic, and spectroscopic studies. Complex 1 displays reversible thermo-induced two-step spin-state switching with two well-separated and gradual transitions at 223 and 137 K. Temperaturedependent X-ray structure analyses confirm the presence of three spin-states HS, LS, and an ordered HS-LS (1:1) intermediate phase in 1 during spin-state switching behavior. An interesting symmetry breaking has been observed with a single iron(II) site in the HS state to two crystallographically different iron(II) sites in an ordered HS-LS state, which shows a re-entrant structural phase-transition process at LS state. Further, Complex 1 exhibits ON/OFF photoswitching between LS state and photo-induced metastable HS state under light irradiation at low temperature. These results highlight that the judiciously chosen ligand and coligand played a significant role in attaining multistability in the SCO system, where greater flexibility allows the control of various stable spin-states with symmetry breaking. The impact of ligand substituents on spin-state switching in analogous iron(II) complexes with the crystallographic characterization of the photo-induced excited state is currently underway in our research group.