A double containment fitting for engagement with double containment pipes and comprising a one-piece integral structure having at least one outer cylinder having at least two outer receiving openings, at least one inner cylinder having at least two inner receiving openings, and a plurality of ribs integral with and spacing the at least one outer cylinder from the at least one inner cylinder, thereby forming an inner fitting flow area within the inner cylinder and forming an outer fitting flow area between the at least one outer cylinder and the at least one inner cylinder and between adjacent ribs. Each inner tube of the double containment pipes are connected to the double containment fitting by being located within one of the inner receiving openings. Each outer tube of the double containment pipes are connected to the double containment fitting by being located within one of the outer receiving openings.