A watercraft lift assembly is provided. The watercraft lift assembly may include a frame, a pair of opposing cantilever arm assemblies and a lifting system. The frame may include a plurality of vertical posts and overhead elements forming a generally simple cubic lattice frame defining a watercraft operational envelope. Each cantilever arm assembly may include a pair of cooperating cantilever arms. Each cantilever arm may be generally L-shaped having a horizontal arm portion and a vertical arm portion slidably secured to an adjacent vertical post. Each horizontal arm portion may include a housing for slidably receiving an extension element. On each cantilever arm assembly, a cantilever bunk may be pivotably connected to the ends of the cooperating extension elements so as to operably engage the bottom surface of various watercrafts when the pair of cantilever arm assemblies moves from a low position to a raised position under the power of the lifting system.