The current Opel Signum is 4,636 mm long, 1,798 mm wide and 1,466 mm tall, on a 2,830 mm wheelbase.
Only one generation of this model is in our catalogue, so there is no size history to compare yet.
Exterior figures are manufacturer specifications for the Signum, averaged per generation across its variants and shown for the most common body style. Generations with the same size are merged. Boot capacity is the seats-up figure where the manufacturer quotes one.