Neptunium(V) fluoride or neptunium pentafluoride is a chemical compound of neptunium and fluorine with the formula NpF<sub>5</sub>.
Neptunium(V) fluoride can be prepared by reacting neptunium(VI) fluoride with iodine:
From the equation above, iodine pentafluoride is a byproduct.
Neptunium(V) fluoride thermally decomposes at 318 ðC to produce neptunium(IV) fluoride and neptunium(VI) fluoride. Contrary to uranium(V) fluoride, neptunium(V) fluoride does not react with boron trichloride, but it reacts with lithium fluoride in anhydrous HF to produce LiNpF<sub>6</sub>.