A bed base has parts adapted to be assembled together manually without the use of a tool or separate, non-integrated connectors. These parts include side members, corner connectors, and a cross-rail assembly. The side members are assembled into a rectangular support and attached at its corners by a male-female connection mechanisms in lower portions of the side members. The corner connectors overlap and lock together the upper portions of adjacent side members at the corners and are attached by male-female connection mechanisms. Each opposed side member includes a notch along an upper portion and the notches in the opposed side members are aligned upon assembly. The cross-rail assembly, which sits across the opposed side members within the notches, has an orthogonal leg member near each end. Each individual leg member projects through a corresponding notch and terminates in one component of two-component connector. The other component of each two-component connector is in the side member with the other component's corresponding notch.