Four (solid-solid) phase transitions were detected in the temperature range of (9 to 300) K in polycrystalline [Cr(NH3)(6)](BF4)(3) at T-C1 = 240.7 K, T-C2 = 108.0 K, T-C3 = 91.9 K, and T-C4 = 61.3 K by adiabatic calorimetry. The measurements by relaxation calorimetry were followed on lowering temperature from 20 K down to 0.35 K under six different external magnetic field values (9, 7, 5, 3, 1 and 0) T. For non-zero values of applied magnetic field well-defined Schottky anomaly appears. Magnetic heat capacity was calculated assuming the zero-field splitting for the decoupled Cr(III) ions. There is no discrepancy between the observed and calculated values. Isothermal magnetization curve recorded up to 5 T was measured at temperature of 1.8 K. (C) 2015 Elsevier Ltd. All rights reserved.