The resonant photodissociation spectrum of supersonically cooled and isolated NbAr+ has been observed in the visible. A vibrational structure of two electronic transitions, labeled here as the B-X and the b-X, are analyzed. Assignment of the diabatic dissociation limits of the b state (Nb+ (4d43G5) + Ar (1S0)) and the B state (Nb+ (4d3 5s5P2) + Ar (1S0)), places the adiabatic binding energy of the ground state of NbAr+ at 3106 ± 10 cm-1. NbAr+ is only slightly more strongly bound (130 cm-1) than the isoelectronic VAr+, and more weakly bound than CoAr+ or NiAr+. Trends in the inductive contribution to the binding of metal ions complexed with argon are presented.