A uniaxial sulphamic acid single crystal having dimensions of 35 mm diameter and 150 mm length was grown. Employing slow evaporation technique sulphamic acid crystals of size 10 x 10 x 5 mm(3) were grown. Etching, microhardness, high-resolution X-ray diffraction, laser damage threshold, UV-visible, Thermogravimetric and differential thermal analysis were made on conventional and the Sankaranarayanan-Ramasamy method grown sulphamic acid crystals. Etching behaviour of the (1 0 0) plane of conventional and the Sankaranarayanan-Ramasamy method grown sulphamic acid crystals was investigated with different etchants. Vicker's microhardness test on the (1 0 0) plane confirmed the mechanical stability of the conventional and the Sankaranarayanan-Ramasamy method grown sulphamic acid crystals. High-resolution X-ray diffraction results show that the crystalline perfection of sulphamic acid single crystals grown by the Sankaranarayanan-Ramasamy method is extremely good compared to the conventional slow evaporation method grown sulphamic acid crystal. Thermogravimetric and differential thermal analysis was carried out to determine the thermal properties of the grown crystal. (C) 2009 Elsevier B.V. All rights reserved.