We present fully differential next-to-leading order results for Higgs production in association with a Z boson in gluon fusion. Our two-loop virtual contributions are evaluated numerically using sector decomposition, including full top-quark mass effects, and supplemented at high p T by an analytic high-energy expansion to order (m 4 Z , m 4 H , m 32 t ). Using the expanded results we also present a study of the top-quark mass scheme uncertainty at large p T .