There is one independent molecule in the asymmetric unit of the title compound (alternatively named N-hydroxyacetamide), C2H5NO2. It crystallizes in the noncentrosymmetric space group P43. The structure is an anhydrous form of acetylhydroxamic acid with typical geometry that corresponds well with the hydrated structure described by Bracher & Small [Acta Cryst. (1970), B26, 1705–1709]. In the crystal, N—H...O and O—H...O hydrogen bonds connect the molecules into chains in the c-axis direction.
