  We consider the decay of the inflaton in Starobinsky-like models arising from
either an $R+R^2$ theory of gravity or $N=1$ no-scale supergravity models. If
Standard Model matter is simply introduced to the $R + R^2$ theory, the
inflaton (which appears when the theory is conformally transformed to the
Einstein frame) couples to matter predominantly in Standard Model Higgs kinetic
terms. This will typically lead to a reheating temperature of $\sim 3 \times
10^9$~GeV. However, if the Standard Model Higgs is conformally coupled to
curvature, the decay rate may be suppressed and vanishes for a conformal
coupling $\xi = 1/6$. Nevertheless, inflaton decays through the conformal
anomaly leading to a reheating temperature of order $10^8$~GeV. The Starobinsky
potential may also arise in no-scale supergravity. In this case, the inflaton
decays if there is a direct coupling of the inflaton to matter in the
superpotential or to gauge fields through the gauge kinetic function. We also
discuss the relation between the theories and demonstrate the correspondence
between the no-scale models and the conformally coupled $R+R^2$ theory (with
$\xi = 1/6$).
