The energy transfer pathways in trimeric and hexameric aggregation states of cyanobacteria C‐phycocyanin (C‐PC) are investigated in the framework of the Förster model at TDDFT/B3LYP/6‐311G* level by Yanliang Ren, Bo Chi, Osama Melhem, Ke Wei, Lingling Feng, Yongjian Li, Xinya Han, Ding Li, Ying Zhang, Jian Wan, Xin Xu, and Minghui Yang on page 1005. When the protonation of phycocyanobilins and their long‐ and short‐range interactions are considered, the calculated energy transfer rates are in good agreement with the experimental results of the C‐PC monomer and trimer. In the C‐PC hexamer, an additional energy flow is predicted from β‐155 in the top trimer to adjacent β‐155 in the bottom trimer.