Less than half an hour to assemble. Very sturdy sofa. We find it very comfortable and we use it daily. 
Only drawback in my mind is that the cushions are not reversible as only one side of the cushions is completely upholstered with the sofa material. The other side is only half upholstered the rest Is covered with a plain black dust cover type upholstery. 
Otherwise, a fantastic, comfortable unit that is easy to dress up or dress down depending on your preferences.