The short answer is: sometimes, but there is no city-wide rule. In most cities, whether urban outdoor furniture arrives fully assembled depends on the product, retailer, delivery route, and building access. Online orders are often flat-packed or partly assembled because couriers and parcel networks are not set up to move bulky, heavy items through narrow hallways, stairwells, and small elevators. A large bench or planter might technically be available assembled, but getting it into a rooftop terrace or courtyard can be another story. Loading zones, service elevators, building management rules, and narrow streets all affect the final delivery method.
That said, fully assembled delivery is common in some situations. Local furniture makers, garden centers, and commercial suppliers often offer white-glove delivery for cafes, parks, office courtyards, and residential buildings. If the item is heavy and the access is clear, they may bring it in already assembled or assemble it on site as part of the service. Public-space projects and bulk commercial orders are also more likely to include assembly, because the buyer needs the furniture ready for use and the delivery team can plan access in advance.
For everyday residential buyers, I would not assume full assembly. Chairs, small tables, and modular pieces are frequently shipped in boxes. Larger items may arrive partly assembled, with legs, bases, or hardware separate. The safest approach is to check the product page, read the delivery notes, and ask whether assembly is included or available. Before ordering, measure doorways, elevators, stair turns, and balcony access. In cities, access—not just the furniture itself—often decides how it will be delivered.