  Since electroweak symmetry is generally broken during inflation, the Standard
Model Higgs field can become supermassive even after the end of inflation. In
this paper, we study the non-thermal phase space distribution of the Higgs
field during reheating, focusing in particular on two different contributions:
primordial condensate and stochastic fluctuations. We obtain their analytic
formulae, which agree with the previous numerical result. As a possible
consequence of the non-thermal Higgs spectrum, we discuss perturbative Higgs
decay during reheating for the case it is kinematically allowed. We find that
the soft-relativistic and hard spectra are dominant in the decay rate of the
stochastic fluctuation and that the primordial condensate and stochastic
fluctuations decay almost at the same time.
