Abstract: A suitably cut and scored blank adapted to be folded for forming a folded envelope and an envelope formed therefrom. The blank and envelope are formed from a sheet of foldable material such as paper cut and scored for defining a planar rectangular main body of predetermined height and width and bounded by three straight side score lines and a cut edge and have at least one vertical score line dividing the main body into at least two body portions of substantially equal height which are hingedly connected one to the other along the vertical score line. Right and left flap panels extend vertically of the main body and are hingedly connected along right and left side score lines for folding leftwardly and rightwardly respectively into juxtaposition with the body portions.