Ammonium cyanate is an inorganic compound with the formula [NH4]+[OCN]−.

The structure of this salt was verified by X-ray crystallography.

The respective C–O and C–N distances are 1.174(8) and 1.192(7) Å, consistent with the O=C=N− description.

Ammonium cation [NH4]+ forms hydrogen bonds with cyanate anion O=C=N−, but to N, not to O.

[2] This led to the discarding of the Vital force theory, suggested earlier by Berzelius.