Primarily 18th-century, with influences from earlier periods.
Royal Zwolle Castle primarily exhibits an 18th-century architectural style, particularly seen in its main facade and prominent features, reflecting the classicist and baroque tastes of the period. However, elements from earlier centuries, dating back to its 14th-century origins, are integrated or can be discerned within the structure, suggesting its gradual evolution. This blend makes the castle an interesting example of architectural layering typical of long-standing European estates, providing a rich visual narrative of its past.