A method for manufacturing a composite assembly with a continuous skin for a rear end of an aircraft by obtaining an upper part of the rear end by composite tooling. The upper part comprises a multi-spar vertical tail plane. The spars of the vertical tail plane comprise widening roots that form an upper shell of the rear end and an upper skin. Furthermore, a lower part comprises a lower shell of the rear end including semi-complete frames and stringers and a lower skin. The upper and lower parts are assembled with a joining procedure. The upper and lower skins are joined to obtain the composite assembly with the continuous skin.