Abstract: A method for producing phosphoryl triamide OP(NH2)3 or thiophosphoryl triamide SP(NH2)3, in which: a) phosphoryl trichloride OPCl3 or thiophosphoryl trichloride SPCl3, respectively, is reacted with gaseous ammonia in an apolar liquid phase to give a first precipitate comprising, respectively, phosphoryl triamide or thiophosphoryl triamide, and ammonium chloride, and b) the first precipitate is treated with sodium carbonate or potassium carbonate, in a polar organic liquid phase, to give a second precipitate comprising NaCl and the phosphoryl triamide or thiophosphoryl triamide remaining in said polar organic liquid phase, and the second precipitate is separated from the polar organic liquid phase, the latter possibly undergoing a further concentration step to enrich it in phosphoryl triamide or thiophosphoryl triamide.