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We report hard x-ray photoemission spectroscopy measurements of the electronic structure of the prototypical correlated oxide ${\mathrm{Sr}}_{x}{\mathrm{Ca}}_{1\ensuremath{-}x}{\mathrm{VO}}_{3}$. By comparing spectra recorded at different excitation energies, we show that 2.2 keV photoelectrons contain a substantial surface component, whereas 4.2 keV photoelectrons originate essentially from the bulk of the sample. Bulk-sensitive measurements of the O $2p$ valence band are found to be in good agreement with ab initio calculations of the electronic structure, with some modest adjustments to the orbital-dependent photoionization cross sections. The evolution of the O $2p$ electronic structure as a function of the Sr content is dominated by $A$-site hybridization. Near the Fermi level, the correlated V $3d$ Hubbard bands are found to evolve in both binding energy and spectral weight as a function of distance from the vacuum interface, revealing higher correlation at the surface than in the bulk.