Abstract: Fitting coupled adiabatic potential energy surfaces using coupled diabatic states enables, for accessible systems, nonadiabatic dynamics to be performed with superior accuracy, when compared with that attainable using on-the-fly dynamics. However on-the-fly dynamics has advantages not the least of which is the ability to compute molecular properties and interactions including electric dipole moments, transition dipole moments and spin-orbit couplings. The availability of these terms extends the range of processes that can be treated with on-the-fly methods. In this work we use the example of fitting electric dipole and transition dipole moments of the 1,2¹A states of ammonia to show how to bring these advantages to the fit-coupled surface method using a diabatic representation.