We report the low-temperature specific heats of NpCu 5− x Pd x (x=0, 0.5, 1.0, and 1.5), the “plus one f-electron” analogs to the well-studied non-Fermi liquid (nFl) system UCu 5− x Pd x . The Np materials were shown to form in the same AuBe 5 structure type as the U pseudobinary alloys. A number of differences between the Np and U materials are found. The magnetic transition at 15K in the U system is evidently suppressed to lower temperatures in the Np analog, and the low-temperature C/T values are strongly enhanced in the NpCu 5− x Pd x (x=1.0 and 1.5) alloys vs. their U counterparts. Finally, NpCu 4 Ni appears to show non-Fermi liquid behavior similar to that of the NpCu 5− x Pd x system, just as UCu 4 Ni is quite similar to UCu 4 Pd in its nFl behavior.