A packing method for producing a rigid package with a hinged lid, which has a top wall with three hollow ribs (12, 13) extending in a U along the perimeter of the top wall; the packing method comprising the steps of: folding an end portion of a blank onto a panel of the blank to form each hollow rib (12; 13); and gluing a fastening tab (16; 19), which forms the end part of the end portion, to the panel to stabilize each hollow rib (12; 13); the packing method being characterized by comprising the further steps of: positioning a contrasting body (36; 39) close to the panel before folding each end portion; folding each end portion about the contrasting body (36; 39) to form the hollow rib (12; 13); extracting the contrasting body (36; 39) from the hollow rib (12; 13) once each end portion is folded; feeding the blank along a straight folding path through a first folding station, where a first hollow rib parallel to the folding path is folded about a first contrasting body, and through a second folding station, where two second hollow ribs perpendicular to the folding path are folded about two respective second contrasting bodies; applying the blank to an article downstream from the first and second folding stations (34, 35); and folding the blank about the article to form the rigid package enclosing the article and having the hinged lid. folding an end portion of a blank onto a panel of the blank to form each hollow rib (12; 13); and gluing a fastening tab (16; 19), which forms the end part of the end portion, to the panel to stabilize each hollow rib (12; 13); the packing method being characterized by comprising the further steps of: positioning a contrasting body (36; 39) close to the panel before folding each end portion; folding each end portion about the contrasting body (36; 39) to form the hollow rib (12; 13); extracting the contrasting body (36; 39) from the hollow rib (12; 13) once each end portion is folded; feeding the blank along a straight folding path through a first folding station, where a first hollow rib parallel to the folding path is folded about a first contrasting body, and through a second folding station, where two second hollow ribs perpendicular to the folding path are folded about two respective second contrasting bodies; applying the blank to an article downstream from the first and second folding stations (34, 35); and folding the blank about the article to form the rigid package enclosing the article and having the hinged lid. positioning a contrasting body (36; 39) close to the panel before folding each end portion; folding each end portion about the contrasting body (36; 39) to form the hollow rib (12; 13); extracting the contrasting body (36; 39) from the hollow rib (12; 13) once each end portion is folded; feeding the blank along a straight folding path through a first folding station, where a first hollow rib parallel to the folding path is folded about a first contrasting body, and through a second folding station, where two second hollow ribs perpendicular to the folding path are folded about two respective second contrasting bodies; applying the blank to an article downstream from the first and second folding stations (34, 35); and folding the blank about the article to form the rigid package enclosing the article and having the hinged lid.