  We study the details of preheating in Palatini Higgs inflation. We show, that
contrary to what happens in the metric formulation of the model, the Universe
does not reheat through the creation of gauge bosons only, but also through the
tachyonic production of Higgs excitations. The latest entropy production
channel turns out to be very efficient and leads to an almost instantaneous
onset of radiation domination after the end of inflation. As compared to the
metric case, this reduces the number of e-folds needed to solve the usual hot
big bang problems while leading to a smaller spectral index for the primordial
spectrum of density perturbations.
