This study tested 6, 8 and 10-inch wrought steel fittings with flowing water to determine their head loss coefficient values. The fittings comprise long elbows, reducing and expansion elbows, Tees, reducing Tees, concentric reducers and expansions. Sixty fittings from seven manufacturers (four manufacturers per fitting) were tested at specified ranges of flow velocities to determine their head loss coefficients. In addition, an uncertainty analysis was conducted to determine the errors associated with the test set-up, the instrumentation, and the procedures used for these tests. This report presents the head loss coefficients of the fittings and their ranges as a function of upstream flow velocity and the Reynolds number.