This study focuses on the preparation, thermophysical properties, and corrosion analysis of a stable capric acid/cetyl alcohol eutectic phase‐change material (PCM) for application in the thermal comfort of buildings. Differential scanning calorimetry is used to investigate the thermal properties of the prepared eutectic PCM, and the results show that the eutectic composition of 70 % capric acid and 30 % cetyl alcohol was suitable for low‐temperature thermal energy storage as it had melting and freezing temperatures of 22.89 and 11.97 °C, respectively. The latent heats of melting and freezing of the eutectic PCM are 144.92 and 145.85 J g−1, respectively. The changes in the melting point and latent heat of the eutectic mixtures over continuous charging/discharging cycles are presented. The accelerated thermal cycling test and FTIR spectra show that the prepared eutectic PCM has a good thermal stability over 1000 thermal cycles. Moreover, corrosion compatibility tests for Cu, Al, and stainless steel 316 samples with the prepared eutectic PCM are discussed, and recommendations for the use of the PCM in the operational environment are presented.