Conformational flexibility and balance between Möbius aromatic and Hückel antiaromatic conformers in [28]hexaphyrins depend on N-fused structure and meso-aryl substituents, revealed by various spectroscopic methods. In particular, the existence of the two conformers has been confirmed for singly-N-fused [28]hexaphyrins by femtosecond time-resolved transient absorption spectroscopy.