The search for new physics in top quark decays at the LHC is reviewed in this
paper. Results from ATLAS [1] and CMS [2] experiments on top quark decays within the
Standard Model are presented together with the measurements of the W boson polarizations
and the study of the structure of the W tb vertex. As a natural step forward, the experimental
status on measurements sensitive to top quark couplings to gauge bosons (γ, Z, W and H) is
reviewed as well as possible top quark decays Beyond the Standard Model (MSSM and FCNC)
