There is disclosed a unit (1) for forming a layer (40) of a batch (2) of groups (3) of articles, comprising a first conveyor (5) adapted to convey a plurality of groups (3) in an abutting relationship; and a second conveyor (6) adapted to separate batch (2) from said remaining groups (3) for a gap (D); unit (1) further comprises manipulating means (9) adapted to manipulate separated batch (2) on an area (4) defined by second conveyor (6), so as to form layer (40).