High resolution spectra of the 0-0 band of the [18.6]3.5 – X(1)4.5 transition of uraniummonofluoride, UF, obtained using a laser ablation spectrometer, showed a perturbation in the upper state. Examination of the Stark and Zeeman effects yielded permanent electric dipole moments of 2.01 and 1.88 D and magnetic g-factors of 3.28 and 3.26 for the ground and excited states, respectively. Both the dipole moment and g-factor of the ground state are in good agreement with  calculations [I. O. Antonov and M. C. Heaven, J. Phys. Chem. A117, 9684 (2013)]. The Zeeman effect results confirm that the ground state arises primarily from the U+(5  37 2 4I)F configuration and suggest several possible configurations for the upper state.