Using the  SANC system we study the one-loop electroweak standard model prediction, including virtual and real photon emissions, for the decays of on-shell vector and scalar bosons B \to f {\bar f} (\gamma ), where B is a vector boson, Z or W, or a Standard Model Higgs. The complete one-loop corrections and exact photon emission matrix element are taken into account. For the phase-space integration, the Monte Carlo technique is used. For Z decay the QED part of the calculation is first cross-checked with the exact one-loop QED prediction of  KORALZ. For Higgs boson and W decays, a comparison is made with the approximate QED calculation of  PHOTOS Monte Carlo. This provides a useful element for the evaluation of the theoretical uncertainty of  PHOTOS, very interesting for its application in ongoing LEP2 and future LC and LHC phenomenology.

PACS numbers: 12.15.Lk, 13.20.Cz