Overexpression of efflux pumps, is a primary mechanism of multidrug resistance in Staphylococcus aureus. This study evaluated grape pomace extracts and their constituent flavonoids as potential efflux pump inhibitors (EPIs) to restore ciprofloxacin susceptibility. RP-HPLC analysis of the extracts identified quercetin, (+)-catechin, and (−)-epicatechin. The synergistic interaction between these agents and ciprofloxacin was assessed using the checkerboard method against three S. aureus strains: NC