Fluoroantimonic acid solution is so reactive that it is challenging to identify media with which it is unreactive.  Materials compatible with fluoroantimonic acid as a solvent include SOClF, and sulfur dioxide; some chlorofluorocarbons have also been used. Containers for HF/SbF are made of PTFE.
Fluoroantimonic acid solutions decompose when heated, generating free hydrogen fluoride gas and liquid antimony pentafluoride at a temperature of 40 °C.
As a superacid, fluoroantimonic acid solutions protonate nearly all organic compounds, often causing dehydrogenation, or dehydration. In 1967, Bickel and Hogeveen showed that 2HF·SbF reacts with isobutane and neopentane to form carbenium ions:
:(CH)CH + H → (CH)C + H
:(CH)C + H → (CH)C + CH
It is also used in the synthesis of tetraxenonogold complexes.