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The shallow Li 1s core level exhibits a surface-to-bulk core level shift for the stoichiometric Li2B4O7 (1 1 0) surface. Angle-resolved photoemission spectroscopy was used to identify Li1s bulk and surface core level components at binding energies –56.5 ± 0.4 and –53.7 ± 0.5 eV, respectively. We find photoemission evidence for surface states of Li2B4O7 (1 1 0) that exist in the gap of the projected bulk density of states. The existence of surface states is consistent with the large surface-to-bulk core level shift for the Li 1s core.