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Achieving single‐component white organic afterglow remains a great challenge owing to the difficulties in simultaneously supporting long‐lived emissions from varied excited states of a molecule for complementary afterglow. Here, an extraordinary tri‐mode emission from the radiative decays of singlet (S1), triplet (T1), and stabilized triplet (T1*) excited states was proposed to afford white afterglow through modulating the singlet–triplet splitting energy (ΔEST) and exciton trapping depth (ETD). Low‐lying T1* for yellow afterglow was constructed by H‐aggregation engineering with large ETD and trace isomer doping, while high‐lying T1 and S1 for blue afterglow with thermally activated emission feature were realized by reducing ΔEST through donor–acceptor molecular design. Therefore, the single‐component white afterglow with high efficiency of 14.1 % and a lifetime of 0.61 s was achieved by rationally regulating the afterglow intensity ratios of complementary emissions from S1, T1, and T1*. [ABSTRACT FROM AUTHOR]