Single crystals of three A xNbO 3 (A = Sr, Ba) reduced niobate cubic perovskites have been obtained by recrystallization of reduced ternary ceramic precursors from borate fluxes under high-vacuum. Product formation could be influenced by variation of the alkaline-earth metal oxide content of the flux, as well as the ternary precursor. The crystallized compounds have been characterized by single crystal X-ray diffraction, showing them to be ideal cubic perovskites with no evidence for long range ordering of the vacancies in the partially occupied A-site.