Extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae are often susceptible in vitro to β-lactam/β-lactamase inhibitor (BLBLI) combination antibiotics, but their use has been limited by concerns of clinical inefficacy. We aimed to compare outcomes between patients treated with BLBLIs and carbapenems for bloodstream infection (BSI) caused by cefotaxime non-susceptible (likely ESBL- or AmpC β-lactamase-producing) Escherichia coli and Klebsiella pneumoniae.