In 2016, our laboratory adopted the 2010 CLSI extended-spectrum cephalosporins (ESC) breakpoint criteria in Enterobacterales. ESBL testing had continued in Blood cultures but discontinued in General Cultures. The aims of this study were to examine the effect of this transition on (1) the resistance rates to ESC; (2) the consumption of parenteral β-lactam antimicrobials, and (3) the therapeutic use of ESC and the outcome of patients infected by ESBL-producing Enterobacterales. In K. pneumoniae and E. coli, the ESC resistance rates had increased, declined or remained unchanged in Urine, General and Blood cultures, respectively. In P. mirabilis, the resistance rates declined for ceftazidime but remained unchanged for ceftriaxone. Carbapenem consumption had not replaced ESC, but the consumption of piperacillin-tazobactam had increased. The use of ESC in suspected ESBL infections had increased slightly, without effect on clinical outcome.