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The structural, magnetic and magnetocaloric properties of several HoFe_2−xAl_x compounds were investigated. The compounds in the Fe-rich region (0.36⩽x⩽0.4) crystallize in the cubic MgCu₂ (C15) structure, while for the ones in the intermediate region (0.75⩽x⩽1.125) the hexagonal MgZn₂ (C14) structure was observed. Electronic structure calculations were performed, showing a good agreement between theory and experiment. The Curie temperatures were found to decrease with Al content. For the Fe-rich compounds, these are close to room temperature, while for the compounds in the intermediate region, transition temperatures are well below 300K. No magnetic hysteresis was found around the Curie temperature for applied magnetic fields of up to 4T. All of the investigated compounds undergo a second-order magnetic phase transition at the Curie temperature. A maximum magnetic entropy change value …