The structural, magnetic and magnetocaloric properties of Ni2Mn1+xIn1−x alloys, prepared using an arc-melting furnace in an argon environment, have been studied for their potential application in cost-effective magnetic refrigeration technology. The room-temperature x-ray diffraction shows that the Ni2Mn1+xIn1−x alloys with 0  ⩽  x  ⩽  0.34 exhibit austenite cubic phase, whereas the alloys with x  >  0.34 have mixed tetragonal martensite and cubic austenite phases. The Ni2Mn1.34In0.66 alloy shows a clear second-order phase transition with a Curie temperature of 305 K but its elemental composition is very close to the critical composition between first and second–order phase transitions. The calculated magnetic entropy change and relative cooling power of the Ni2Mn1.34In0.66 alloy measured at 3 T field are 4.5 J kg−1 K−1 and 201 J kg−1, respectively. The temperature dependent resistivity of Ni2Mn1.34In0.66 alloy measured at H  =  0 Oe shows that the sample has a room temperature resistivity of 7 The absence of thermal and magnetic hysteresis due to second-order magnetic phase change, coupled with higher values of magnetic entropy change and relative cooling power, suggests that the Ni2Mn1.34In0.66 alloy has the potential for magnetic refrigeration.