ABSTRACT. We prove sharp regularity estimates for viscosity solutions of fully nonlinear parabolic equations of the formwhere F is elliptic with respect to the Hessian argument and f ∈ L p,q (Q 1 ). The quantity κ(n, p,q) := n p + 2 q determines to which regularity regime a solution of (Eq) belongs. We prove that when 1 < κ(n, p,q) < 2 − ε F , solutions are parabolic-Hölder continuous for a sharp, quantitative exponent 0 < α(n, p,q) < 1. Precisely at the critical borderline case, κ(n, p,q) = 1, we obtain sharp Log-Lipschitz regularity estimates. When 0 < κ(n, p,q) < 1, solutions are locally of class C 1+σ, 1+σ 2 and in the limiting case κ(n, p,q) = 0, we show C 1,Log-Lip regularity estimates provided F has "better" a priori estimates.