Ammonium hexafluoroaluminate is an inorganic compound with the chemical formula of (NH<sub>4</sub>)<sub>3</sub>[AlF<sub>6</sub>]. It is a white solid. Upon heating, it converts to aluminium trifluoride, a reaction that releases hydrogen fluoride. It has also been used as a precursor to zeolites.
Ammonium hexafluoroaluminate can be obtained by the reaction of ammonium fluoride and aluminium hydroxide.