It crystallizes as small colourless prisms, having a sharp saline taste, and is highly soluble in water.

[3] This structure is very similar to ice, and ammonium fluoride is the only substance which can form mixed crystals with water.

For this reason it cannot be handled in glass test tubes or apparatus during laboratory work.

Ammonium fluoride is a critical component of buffered oxide etch (BOE), a wet etchant used in microfabrication.

[5] It is also used for preserving wood, as a mothproofing agent, in printing and dyeing textiles, and as an antiseptic in breweries.