Abstract: Systems for coupling two or more watercrafts, and assemblies comprised of systems and watercrafts. A watercraft coupling system includes a forward connector rod and an aft connector rod that are configured to be attached to forward and aft portions of adjacent first and second watercrafts, and may include additional components such as stabilization straps, nets, and rod cushions for safety and comfort. The system may be used to stably couple two or more watercrafts, such as recreational watercrafts, in a side-by-side arrangement to form a watercraft assembly that may be used by two or more users cooperatively.