We present spectra of prompt electrons from decays of neutral and charged B mesons. The results are based on 140 fb−1 of data collected by the Belle detector on the resonance at the KEKB asymmetric collider. We tag events by reconstructing a B meson in one of several hadronic decay modes; the semileptonic decay of the other B meson is inferred from the presence of an identified electron. We obtain for charged and neutral B mesons the partial rates of semileptonic decay, to electrons with momentum greater than in the B rest frame, and their ratio , where the first and second errors are statistical and systematic, respectively.