This article reports the performance of alloyed Ohmic contacts to Ga(1-X)In-(X)As/InP composite channel InP high electron mobility transistors for various indium compositions, from X=35% to X=81%. Both strained and pseudomorphic structures were utilized to observe the impact of the indium concentration on electron mobility, carrier concentration, sheet resistance, and specific contact resistance. The lowest specific contact resistance (Rt<0.16 Ohm mm) was obtained for strained structures with indium concentrations of 74% and 81%. For strained structures with indium concentrations of 35%, we observe specific contact resistance of 0.35 Ohm mm.