Spin-orbit configuration interaction (SO-CI) and coupled-cluster [CCSDT(Q)] theoretical methods are combined to evaluate zero-temperature thermochemical properties of PtH, PtH+, and PtH-. We obtain vibrational zero-point energies and spin-orbit stabilization energies, which lead to predictions for observable quantities: ionization energy IE(PtH) = (9.44 ± 0.07) eV; electron affinity EA(PtH) = (1.65 ± 0.04) eV; and dissociation energies D0(Pt-H) = (329.6 ± 3.9) kJ mol-1, D0(Pt+-H) = (279.3 ± 5.7) kJ mol-1, and D0(Pt--H) = (285.0 ± 2.4) kJ mol-1 (uncertainty coverage factor = 2). Compared with available experiments, our value of D0(Pt+-H) is higher by (8 ± 8) kJ mol-1, EA(PtH) is higher by 0.15eV, and D0(Pt-H) is lower than the upper bound by (2 ± 4) kJ mol-1.