  We systematically study and classify scotogenic models with a local U(1)
gauge symmetry. These models give rise to radiative neutrino masses and a
stable dark matter candidate, but avoid the theoretical problems of global and
discrete symmetries. We restrict the dark sector particle content to up to four
scalar or fermionic SU(2) singlets, doublets or triplets and use theoretical
arguments based on anomaly freedom, Lorentz and gauge symmetry to find all
possible charge assignments of these particles. The U(1) symmetry can be broken
by a new Higgs boson to a residual discrete symmetry, that still stabilizes the
dark matter candidate. We list the particle content and charge assignments of
all non-equivalent models. Specific examples in our class of models that have
been studied previously in the literature are the U(1)$_D$ scotogenic and
singlet-triplet scalar models breaking to $Z_2$. We also briefly discuss the
new phenomenological aspects of our model arising from the presence of a new
massless dark photon or massive $Z'$ boson as well as the additional Higgs
boson.
