The PSiP pincer-supported complex ((PSiP)-P-Cy)PdH [(PSiP)-P-Cy = Si(Me)(2-PCy2-C6H4)(2)] has been implicated as a crucial intermediate in carboxylation of both allenes and boranes. At this stage, however, there is uncertainty regarding the exact structure of ((PSiP)-P-Cy)PdH, especially in solution. Previously, both a Pd(II) structure with a terminal Pd hydride and a Pd(0) structure featuring an eta(2)-silane have been proposed. In this contribution, a range of techniques were used to establish that ((PSiP)-P-Cy)PdH and the related Pt species, ((PSiP)-P-Cy)PtH, are true M(II) hydrides in both the solid state and solution. The single-crystal X-ray structures of ((PSiP)-P-Cy)MH (M = Pd and Pt) and the related species ((SiP)-Si-iPr)PdH [(PSiP)-P-iPr = Si(Me)(2-(PPr2)-Pr-i-C6H4)(2)] are in agreement with the presence of a terminal metal hydride, and the exact geometry of ((PSiP)-P-Cy)PtH was confirmed using neutron diffraction. The H-1 and Si-29{H-1}NMR chemical shifts of ((PSiP)-P-Cy)MH (M = Pd and Pt) are consistent with a structure containing a terminal hydride, especially when compared to the chemical shifts of related pincer-supported complexes. In fact, in this work, two general trends relating to the H-1 NMR chemical shifts of group 10 pincer-supported terminal hydrides were elucidated: (i) the hydride shift moves downfield from Ni to Pd to Pt and (ii) the hydride shift moves downfield with more trans-influencing pincer central donors. DFT calculations indicate that structures containing a M(II) hydride are lower in energy than the corresponding eta(2)-silane isomers. Furthermore, the calculated NMR chemical shifts of the M(II) hydrides using a relativistic four-component methodology incorporating all significant scalar and spin-orbit corrections are consistent with those observed experimentally. Finally, in situ X-ray absorption spectroscopy (XAS) was used to provide further support that ((PSiP)-P-Cy)MH exist as M(II) hydrides in solution.